Substituted dihydropyrrolopyrazole compound

(S)—N-(2-Hydroxy-1-phenylethyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. IV-114)

To a solution of 308 mg (0.698 mmol) of ethyl 5-(chlorocarbonyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 3 in 6 ml of THF, 0.23 ml (1.4 mmol) of DIPEA and 472 mg (3.44 mmol) of (S)-(+)-2-phenylglycinol were added at room temperature, then applied to a microwave reaction apparatus, and reacted at 80° C. for 1 hour. Subsequently, 2.7 ml (67 mmol) of methanol and 2.7 ml (19 mmol) of triethylamine were added to the reaction solution, then applied to a microwave reaction apparatus, and reacted at 80° C. for 0.5 hours.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: 1,2-dichloroethane:methanol=100:0 to 98:2 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. For the obtained concentration residue, crystallization was performed with ethyl acetate/diethyl ether, and the obtained solid was collected by filtration. 20 ml of water was added to the obtained solid and stirred, and then, insoluble matter was collected by filtration and dried under reduced pressure to obtain 152 mg of the title compound (yield: 46%) as a white solid.

Mass spectrum (DUIS, m/z): 470 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.20 & 11.65 (br s, total 1H), 9.66-9.46 (m, 1H), 7.41-7.25 (m, 4H), 7.22-7.15 (m, 1H), 6.18 & 6.06 (d, J=7.7 Hz, total 1H), 4.88 (t, J=5.9 Hz, 1H), 4.83-4.71 (m, 1H), 4.62-4.41 (m, 2H), 3.69-3.52 (m, 2H), 2.49-2.41 (m, 2H), 2.30-2.12 (m, 2H), 1.93-1.73 (m, 2H), 1.68-1.44 (m, 6H), 0.17-0.04 (m, 9H).

(S)—N-(2-Hydroxy-1-phenylethyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclopropanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. III-114)

To a solution of 433 mg (1.08 mmol) of ethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclopropanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate hydrochloride synthesized in the similar manner as in Reference Example 7 in 7.5 ml of dehydrated dichloromethane, 0.90 ml (5.2 mmol) of DIPEA was added at room temperature in a nitrogen atmosphere, and then, a solution of 275 mg (0.928 mmol) of bis(trichloromethyl)carbonate in 2.5 ml of dehydrated dichloromethane was added dropwise at −78° C. and stirred at the same temperature as above for 2.5 hours.

After the completion of the reaction, 10 ml of a saturated aqueous solution of sodium bicarbonate was added to the reaction solution and stirred while the temperature was raised to room temperature for a while. The organic layer and the aqueous layer were separated, and then, the aqueous layer was subjected to extraction with dichloromethane twice. All of the obtained organic layers were dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (elution solvent: n-hexane:ethyl acetate=90:10 to 80:20 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure and dried under reduced pressure to obtain a concentration residue.

To a solution of 457 mg of the obtained concentration residue in 4 ml of dehydrated THF, 0.40 ml (2.2 mmol) of DIPEA and 528 mg (3.85 mmol) of (S)-(+)-2-phenylglycinol were added at room temperature in a nitrogen atmosphere and then stirred for 3.75 hours while heated to reflux. Subsequently, 0.90 ml (6.5 mmol) of triethylamine and 0.90 ml (22 mmol) of methanol were added to the reaction solution and then stirred for 1 hour while heated to reflux.

After the completion of the reaction, water was added to the reaction solution, followed by extraction with dichloromethane three times. All of the obtained organic layers were dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DNH silica gel, elution solvent: dichloromethane:methanol=100:0 to 97:3 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. For the obtained concentration residue, crystallization was performed with ethyl acetate/diisopropyl ether/n-hexane, and the deposited solid was collected by filtration, washed by sousing with n-hexane, and then dried under reduced pressure to obtain 388 mg of the title compound (yield: 79% [2 steps]) as a white solid.

Mass spectrum (CI, m/z): 456 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.02 & 11.54 (br s, total 1H), 9.44 & 9.25 (br s, total 1H), 7.40-7.33 (m, 2H), 7.33-7.24 (m, 2H), 7.23-7.16 (m, 1H), 5.88-5.69 (m, 1H), 4.86-4.79 (m, 1H), 4.61 (t, J=5.6 Hz, 1H), 4.55-4.37 (m, 2H), 3.71-3.64 (m, 2H), 1.63 (s, 3H), 1.57 (s, 3H), 1.08-1.01 (m, 2H), 0.83-0.60 (m, 2H), 0.07 (s, 9H).

(S)—N-(2-Hydroxy-1-phenylethyl)-6,6-dimethyl-3-[2-methyl-2-(trimethylsilyl)propanamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. II-114)

To a solution of 337 mg (0.714 mmol) of 5-tert-butyl 1-ethyl 6,6-dimethyl-3-[2-methyl-2-(trimethylsilyl)propanamido]pyrrolo[3,4-c]pyrazole-1,5(4H,6H)-dicarboxylate synthesized in the similar manner as in Reference Example 9 in 3 ml of dehydrated dichloromethane, 0.25 ml (2.2 mmol) of 2,6-lutidine and 0.39 ml (2.2 mmol) of trimethylsilyl trifluoromethanesulfonate were added in this order at 0° C. in a nitrogen atmosphere and stirred at the same temperature as above for 1.5 hours.

After the completion of the reaction, the reaction solution was diluted with dichloromethane and subsequently washed with a saturated aqueous solution of sodium bicarbonate. The organic layer and the aqueous layer were separated, and then, the aqueous layer was subjected to extraction with dichloromethane twice. All of the obtained organic layers were dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The operation of adding 25 ml of toluene to the obtained concentration residue and concentrating it under reduced pressure was repeated three times, followed by drying under reduced pressure to obtain a concentration residue.

To a solution of 292 mg of the obtained concentration residue in 5 ml of dehydrated dichloromethane, 0.38 ml (2.2 mmol) of DIPEA was added at room temperature in a nitrogen atmosphere, and then, 149 mg (0.502 mmol) of bis(trichloromethyl)carbonate was added at −78° C. and stirred at the same temperature as above for 2.5 hours.

After the completion of the reaction, 7 ml of a saturated aqueous solution of sodium bicarbonate was added to the reaction solution and stirred while the temperature was raised to room temperature for a while. The organic layer and the aqueous layer were separated, and then, the aqueous layer was subjected to extraction with dichloromethane once. All of the organic layers were dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (elution solvent: n-hexane:ethyl acetate=90:10 to 85:15 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure and dried under reduced pressure to obtain a concentration residue.

To a solution of 262 mg of the obtained concentration residue in 3 ml of dehydrated THF, 0.27 ml (1.6 mmol) of DIPEA and 255 mg (1.86 mmol) of (S)-(+)-2-phenylglycinol were added at room temperature in a nitrogen atmosphere and then stirred for 2.5 hours while heated to reflux. Subsequently, 1.0 ml (7.2 mmol) of triethylamine and 1.0 ml (25 mmol) of methanol were added to the reaction solution and then stirred for 5.5 hours while heated to reflux.

After the completion of the reaction, water was added to the reaction solution, followed by extraction with dichloromethane three times. All of the obtained organic layers were dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. 0.10 ml of acetic acid was added to the obtained concentration residue and then subjected to silica gel column chromatography (DIOL silica gel, elution solvent: dichloromethane:methanol=100:0 to 97:3 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. For the obtained concentration residue, crystallization was performed with ethyl acetate/n-hexane, and the obtained solid was collected by filtration, washed by sousing with n-hexane, and then dried under reduced pressure to obtain 206 mg of the title compound (yield: 63% [3 steps]) as a pale yellow solid.

Mass spectrum (CI, m/z): 458 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.25 & 11.64 (br s, total 1H), 9.42-9.11 (m, 1H), 7.38-7.25 (m, 4H), 7.23-7.15 (m, 1H), 6.21-6.05 (m, 1H), 4.87 (t, J=5.9 Hz, 1H), 4.81-4.73 (m, 1H), 4.57-4.41 (m, 2H), 3.70-3.54 (m, 2H), 1.66-1.47 (m, 6H), 1.25 (s, 6H), 0.04 (s, 9H).

(S)-3-[1-(Ethyldimethylsilyl)cyclobutanecarboxamido]-N-(2-hydroxy-1-phenylethyl)-6,6-dimethyl-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. IV-117)

To a solution of 454 mg (0.997 mmol) of ethyl 5-(chlorocarbonyl)-3-[1-(ethyldimethylsilyl)cyclobutanecarboxamido]-6,6-dimethyl-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 13 in 10 ml of dehydrated THF, 700 mg (5.10 mmol) of (S)-(+)-2-phenylglycinol and 0.35 ml (2.0 mmol) of DIPEA were added at room temperature in an argon atmosphere and then stirred at 60° C. for 4 hours. Subsequently, 6 ml of methanol and 2 ml of triethylamine were added to the reaction solution and stirred at 60° C. for 2 hours.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure, a saturated aqueous solution of sodium bicarbonate was added to the obtained concentration residue, and the mixed solution was subjected to extraction with dichloromethane three times. All of the obtained organic layers were dried over anhydrous magnesium sulfate and filtered, and then, the filtrate was concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: 1,2-dichloroethane:methanol=100:0 to 98:2 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. For the concentration residue, crystallization was performed with dichloromethane/diisopropyl ether, and the deposited solid was collected by filtration and subsequently dried under reduced pressure to obtain 404 mg of the title compound (yield: 84%) as a white solid.

Mass spectrum (DUIS, m/z): 484 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.20 & 11.66 (br s, total 1H), 9.64-9.47 (m, 1H), 7.40-7.14 (m, 5H), 6.26-6.01 (m, 1H), 4.88 (t, J=5.8 Hz, 1H), 4.83-4.71 (m, 1H), 4.60-4.43 (m, 2H), 3.66-3.54 (m, 2H), 2.48-2.42 (m, 2H), 2.33-2.14 (m, 2H), 1.93-1.72 (m, 2H), 1.67-1.45 (m, 6H), 0.92 (t, J=7.9 Hz, 3H), 0.60 (q, J=7.9 Hz, 2H), 0.08 (s, 6H).

(S)-3-[2-(Ethyldimethylsilyl)-2-methylpropanamido]-N-(2-hydroxy-1-phenylethyl)-6,6-dimethyl-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. II-116)

To a solution of 2.44 g (6.41 mmol) of ethyl 3-[2-(ethyldimethylsilyl)-2-methylpropanamido]-6,6-dimethyl-5,6-dihydropyrrolo[3,4-c]pyrazole-1(4H)-carboxylate synthesized in the similar manner as in Reference Example 16 in 30 ml of dehydrated dichloromethane, 5.6 ml (32 mmol) of DIPEA and a solution of 1.33 g (4.48 mmol) of bis(trichloromethyl)carbonate in 10 ml of dehydrated dichloromethane were added in this order at −78° C. in a nitrogen atmosphere and stirred at the same temperature as above for 1 hour.

After the completion of the reaction, a saturated aqueous solution of sodium bicarbonate was added to the reaction solution, and the temperature was raised to room temperature for a while with stirring. After separation into an aqueous layer and an organic layer, the aqueous layer was subjected to extraction with dichloromethane. All of the obtained organic layers were dried over anhydrous magnesium sulfate and filtered, and the filtrate was concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (elution solvent: n-hexane:ethyl acetate=95:5 to 70:30 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure to obtain 2.51 g of a concentration residue.

To a solution of 474 mg of the obtained concentration residue in ml of dehydrated THF, 700 mg (5.10 mmol) of (S)-2-amino-2-phenylethanol and 0.35 ml (2.0 mmol) of DIPEA were added at room temperature in an argon atmosphere, then applied to a microwave reaction apparatus, and reacted at 100° C. for 2 hours. After standing to cool, 6 ml of methanol and 2 ml of triethylamine were added, applied to a microwave reaction apparatus, and reacted at 80° C. for 3 hours.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure, a saturated aqueous solution of sodium bicarbonate was added to the obtained concentration residue, and the mixed solution was subjected to extraction with dichloromethane three times. All of the obtained organic layers were dried over anhydrous magnesium sulfate and filtered, and the filtrate was concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: 1,2-dichloroethane:methanol=100:0 to 98:2 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. For the concentration residue, crystallization was performed with dichloromethane/diisopropyl ether, and the deposited solid was collected by filtration and subsequently dried under reduced pressure to obtain 321 mg of the title compound (yield: 56% [2 steps]) as a white solid.

Mass spectrum (DUIS, m/z): 472 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.26 & 11.67 (br s, total 1H), 9.42-9.16 (m, 1H), 7.38-7.25 (m, 4H), 7.25-7.14 (m, 1H), 6.20-6.04 (m, 1H), 4.88 (t, J=5.8 Hz, 1H), 4.82-4.72 (m, 1H), 4.55-4.42 (m, 2H), 3.66-3.55 (m, 2H), 1.64-1.48 (m, 6H), 1.26 (s, 6H), 0.90 (t, J=7.9 Hz, 3H), 0.56 (q, J=7.9 Hz, 2H), 0.02 (s, 6H).

(S)—N-(2-Hydroxy-1-phenylethyl)-N,6,6-trimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. IV-119)

To a solution of 210 mg (1.39 mmol) of (S)-2-(methylamino)-2-phenylethanol [synthesized according to the method described in J. Org. Chem., 1992, 57, 5383-5394] in 3 ml of dehydrated 1,4-dioxane, 0.24 ml (1.37 mmol) of DIPEA and 200 mg (0.454 mmol) of ethyl 5-(chlorocarbonyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 3 were added in an argon atmosphere and stirred at 100° C. for 3 hours. Subsequently, 1 ml of triethylamine and 1 ml of methanol were added to the reaction solution and stirred at room temperature for 16 hours.

After the completion of the reaction, water was added to the reaction solution, followed by extraction from the mixed solution with ethyl acetate. The obtained organic layer was washed with a saturated aqueous solution of sodium chloride, dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel chromatography (elution solvent: n-hexane:ethyl acetate=90:10 to 0:100 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was subjected again to silica gel chromatography (elution solvent: n-hexane:ethyl acetate=50:50 to 0:100 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was repulp-washed in hexane, and the solid was collected by filtration and then dried under reduced pressure to obtain 105 mg of the title compound (yield: 48%) as a white solid.

Mass spectrum (CI, m/z): 484 [M+1] +

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.21 & 11.84 (br s, total 1H), 9.75-9.42 (m, 1H), 7.41-7.21 (m, 5H), 4.85 (t, J=5.2 Hz, 1H), 4.82-4.76 (m, 1H), 4.58-4.35 (m, 2H), 3.96-3.78 (m, 2H), 2.52 (s, 3H), 2.47-2.38 (m, 2H), 2.23-2.11 (m, 2H), 1.87-1.72 (m, 2H), 1.71-1.52 (m, 6H), 0.05 (s, 9H).

(S)-2-[(2-Methoxypropan-2-yl)oxy]-1-phenylethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxylate (Compound No. VI-360)

To 205 mg of crude ethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-1(4H)-carboxylate [containing impurities] obtained through the same reaction as in Reference Example 5 from 225 mg (0.470 mmol) of 5-tert-butyl 1-ethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]pyrrolo[3,4-c]pyrazole-1,5(4H,6H)-dicarboxylate synthesized in the similar manner as in Reference Example 4, a solution of 187 mg (0.533 mmol) of (S)-2,5-dioxopyrrolidin-1-yl {2-[(2-methoxypropan-2-yl)oxy]-1-phenylethyl}carbonate synthesized in the similar manner as in Reference Example 18 in 3 ml of THF and 0.28 ml (1.6 mmol) of DIPEA were added at room temperature in a nitrogen atmosphere and stirred at the same temperature as above for 15 hours. Subsequently, 1.0 ml (7.2 mmol) of triethylamine and 0.70 ml (17 mmol) of methanol were added to the reaction solution and stirred at room temperature 4.5 hours and for 2 hours while heated to reflux, and then, 247 mg (1.80 mmol) of (S)-2-amino-2-phenylethanol was added to the reaction solution and stirred for 4.5 hours while heated to reflux.

After the completion of the reaction, water was added to the reaction solution, followed by extraction with dichloromethane three times. All of the obtained organic layers were dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (elution solvent: n-hexane:ethyl acetate=80:20 to 50:50 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. For the obtained concentration residue, crystallization was performed with ethyl acetate/n-hexane, and the deposited solid was collected by filtration, washed by sousing with n-hexane, and then dried under reduced pressure to obtain 22.7 mg of the title compound (yield: 9% [2 steps]) as a white solid. The filtrate was further concentrated under reduced pressure and dried under reduced pressure to obtain 178 mg of the title compound (yield: 70% [2 steps]) as a white foam.

Mass spectrum (ESI, m/z): 565 [M+23(Na)] + , 541 [M−1] − .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.35-12.19 & 11.96-11.80 (m, total 1H), 9.85-9.44 (m, 1H), 7.45-7.26 (m, 5H), 5.81-5.68 (m, 1H), 4.63-4.18 (m, 2H), 3.72-3.50 (m, 2H), 3.08-2.94 (m, 3H), 2.56-2.38 (m, 2H), 2.30-2.10 (m, 2H), 1.94-1.75 (m, 2H), 1.73-1.45 (m, 6H), 1.32-1.18 (m, 6H), 0.13-0.02 (m, 9H).

(S)-2-Hydroxy-1-phenylethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxylate (Compound No. IV-2)

To a solution of 175 mg (0.322 mmol) of (S)-2-[(2-methoxypropan-2-yl)oxy]-1-phenylethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxylate synthesized in the similar manner as in Example 7 in 2.5 ml of methanol, 9.6 mg (0.038 mmol) of pyridinium p-toluenesulfonate was added at 0° C. in a nitrogen atmosphere and stirred at the same temperature as above for 70 minutes.

After the completion of the reaction, 0.1 ml of triethylamine was added to the reaction solution and then concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (elution solvent: n-hexane:ethyl acetate=65:35 to 25:75 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. For the obtained concentration residue, crystallization was performed with ethyl acetate/n-hexane, and the deposited solid was collected by filtration, washed by sousing with n-hexane, and then dried under reduced pressure to obtain 124 mg of the title compound (yield: 82%) as a white solid.

Mass spectrum (CI, m/z): 471 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.35-12.11 & 11.97-11.79 (m, total 1H), 9.84-9.46 (m, 1H), 7.46-7.20 (m, 5H), 5.71-5.58 (m, 1H), 5.12-4.95 (m, 1H), 4.72-4.18 (m, 2H), 3.80-3.54 (m, 2H), 2.60-2.38 (m, 2H), 2.30-2.10 (m, 2H), 1.93-1.74 (m, 2H), 1.74-1.43 (m, 6H), 0.16-0.02 (m, 9H).

2-Methoxy-1-phenylethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclopropanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxylate (Compound No. III-5)

To a solution of 2.15 g (5.36 mmol) of ethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclopropanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate hydrochloride synthesized in the similar manner as in Reference Example 7 in 72 ml of dehydrated dichloromethane, 3.6 ml (21 mmol) of DIPEA was added at room temperature and subsequently cooled in a dry ice/acetone coolant, and then, a solution of 1.17 g (3.94 mmol) of bis(trichloromethyl)carbonate in 12 ml of dehydrated dichloromethane was added dropwise over 30 minutes and stirred at the same temperature as above for 6 hours. During this reaction, 3.6 ml (21 mmol) of DIPEA 4 times and DIPEA (1.0 ml, 5.7 mmol) once were added in this order.

After the completion of the reaction, 46 ml of a saturated aqueous solution of sodium bicarbonate was added at −78° C., and then, the temperature was raised to room temperature for a while. The reaction solution was separated into an aqueous layer and an organic layer, then the aqueous layer was subjected to extraction with 50 ml of dichloromethane twice, all of the obtained organic layers were dried over anhydrous magnesium sulfate and filtered, and then, the filtrate was concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (elution solvent: n-hexane:ethyl acetate=78:22 to 57:43 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. 20 ml of n-hexane was added to the concentration residue and cooled in ice, and then, the deposited solid was collected by filtration and dried under reduced pressure to obtain 1.96 g of white solid.

To 40.4 mg (0.0946 mmol) of the obtained white solid, 224 mg (1.48 mmol) of 2-methoxy-1-phenylethanol [synthesized according to the method described in WO 2012/138648], 26.0 mg (0.188 mmol) of potassium carbonate, 0.8 ml of 1,2-dimethoxyethane, and 80 mg of molecular sieve 4 A (powder) were added at room temperature and then stirred at 80° C. for 26 hours.

After the completion of the reaction, insoluble matter was filtered, and 10 ml of ethyl acetate, 5 ml of water, and 5 ml of a saturated aqueous solution of sodium chloride were added to the filtrate and then the aqueous layer and the organic layer were separated. The obtained organic layer was dried over anhydrous magnesium sulfate and filtered, and then, the filtrate was concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography four times (silica gel (1st run), elution solvent: 1,2-dichloroethane:methanol=100:0 to 93:7 (V/V); silica gel (2nd run), elution solvent: ethyl acetate:methanol=98:2 to 95:5 (V/V); silica gel (3rd run), elution solvent: 1,2-dichloroethane:methanol=98:2 to 95:5 (V/V); and DNH silica gel, elution solvent: 1,2-dichloroethane:methanol=98:2 to 95:5 (V/V)) and preparative HPLC (column: X-Bridge (trade name) ODS, elution solvent: 0.1% aqueous formic acid solution: 0.1% formic acid:acetonitrile=50:50 to 5:95 (V/V))), and a fraction containing the compound of interest was neutralized with dilute aqueous ammonia solution and then concentrated under reduced pressure. The obtained concentration residue was dissolved by adding acetonitrile and water and then freeze-dried to obtain 4.1 mg of the title compound (yield: 8% [2 steps]) as a white foam.

Mass spectrum (DUIS, m/z): 471 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.40-11.86 (m, 1H), 10.11-9.61 (m, 1H), 7.49-7.22 (m, 5H), 5.90-5.71 (m, 1H), 4.63-4.14 (m, 2H), 3.77-3.51 (m, 2H), 3.30-3.29 (m, 3H), 1.78-1.40 (m, 6H), 1.11-0.92 (m, 2H), 0.81-0.59 (m, 2H), 0.11-0.04 (m, 9H).

N-[5-(4-Hydroxy-3-phenylbutanoyl)-6,6-dimethyl-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazol-3-yl]-1-(trimethylsilyl)cyclobutanecarboxamide (Compound No. IV-558)

To a solution of 160 mg (0.536 mmol) of ethyl 4-(benzyloxy)-3-phenylbutanoate synthesized in the similar manner as in Reference Example 19 in a mixture of 3 ml of THF/1.5 ml of water, 48 mg (1.1 mmol) of lithium hydroxide monohydrate was added at room temperature in an argon atmosphere, stirred at the same temperature as above for 2 hours, and then stirred at 60° C. for 3 hours. The reaction solution was concentrated under reduced pressure, and 3 ml of ethanol and 1.0 ml (2.0 mmol) of a 2 N aqueous sodium hydroxide solution were added to the obtained concentration residue at room temperature and heated and stirred at 60° C. for 1 hour.

After the completion of the reaction, 1 N hydrochloric acid was added to the reaction solution, followed by extraction from the mixed solution with ethyl acetate. The obtained organic layer was washed with a saturated aqueous solution of sodium chloride, then dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel chromatography (elution solvent: n-hexane:ethyl acetate=90:10 to 50:50 (V/V)), and a fraction containing 4-(benzyloxy)-3-phenylbutanoic acid was concentrated under reduced pressure and dried under reduced pressure to obtain a concentration residue.

To a solution of 137 mg of the obtained concentration residue, 165 mg (0.436 mmol) of ethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-1(4H)-carboxylate synthesized in the similar manner as in Reference Example 5, and 201 mg (0.529 mmol) of O-(7-azabenzotriazol-1-yl)-N,N,N′,N′-tetramethyluronium hexafluorophosphate in 3 ml of dehydrated dichloromethane, 0.185 ml (1.06 mmol) of DIPEA was added at room temperature in an argon atmosphere and stirred at room temperature for 16 hours.

After the completion of the reaction, water was added to the reaction solution, followed by extraction from the mixed solution with ethyl acetate. The obtained organic layer was washed with a saturated aqueous solution of sodium chloride, then dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure. The obtained residue was subjected to silica gel chromatography (elution solvent: n-hexane:ethyl acetate=70:30 to 0:100 (V/V)), and a fraction containing ethyl 5-[4-(benzyloxy)-3-phenylbutanoyl]-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-1 (4H)-carboxylate was concentrated under reduced pressure and dried under reduced pressure to obtain a concentration residue.

To a solution of 256 mg of the obtained concentration residue in a mixture of 2 ml of THF/2 ml of methanol, 2 ml of triethylamine was added at room temperature in an argon atmosphere and stirred at the same temperature as above for 16 hours. Subsequently, 0.20 ml (3.3 mmol) of 2-aminoethanol was added at room temperature and stirred at the same temperature as above for 30 minutes.

After the completion of the reaction, water was added to the reaction solution, followed by extraction from the mixed solution with ethyl acetate. The obtained organic layer was washed with a saturated aqueous solution of sodium chloride, then dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure to obtain a concentration residue.

To a solution of 250 mg of the obtained concentration residue in 3 ml of ethanol, 25 mg of 20% palladium hydroxide/carbon (containing 50% water) was added in an argon atmosphere and after replacement with a hydrogen atmosphere under reduced pressure, stirred at room temperature for 2 hours.

After the completion of the reaction, replacement with an argon atmosphere was performed, and the reaction solution was filtered through celite. The solid on the celite was washed with ethanol, and all of the filtrates were concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=50:50 to 0:100 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure and dried under reduced pressure to obtain 93 mg of the title compound (yield: 45% [3 steps]) as a white solid.

Mass spectrum (CI, m/z): 469 [M+1] +

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.19 & 11.83 (br s, total 1H), 9.84-9.47 (m, 1H), 7.27-7.21 (m, 4H), 7.18-7.12 (m, 1H), 4.72 (t, J=5.3 Hz, 1H), 4.57 (d, J=12.4 Hz, 1H), 4.44 (d, J=12.4 Hz, 1H), 3.60-3.52 (m, 2H), 3.27-3.19 (m, 1H), 2.75 (dd, J=6.0, 15.9 Hz, 1H), 2.58-2.52 (m, 1H), 2.48-2.40 (m, 2H), 2.25-2.12 (m, 2H), 1.89-1.72 (m, 2H), 1.61 (s, 3H), 1.49 (s, 3H), 0.08 (s, 9H).

N-[5-(3-Hydroxy-3-phenylpropanoyl)-6,6-dimethyl-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazol-3-yl]-1-(trimethylsilyl)cyclobutanecarboxamide (Compound No. IV-562)

To a solution of 285 mg (0.543 mmol) of a mixture of ethyl 6,6-dimethyl-5-(3-oxo-3-phenylpropanoyl)-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylat e synthesized in the similar manner as in Reference Example 20 and (Z)-ethyl 5-(3-hydroxy-3-phenylacryloyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate as a tautomer in 5 ml of methanol, 9.2 mg (0.24 mmol) of sodium borohydride was added at 0° C. in a nitrogen atmosphere and stirred for 1.5 hours after the temperature was raised to room temperature.

After the completion of the reaction, 10 ml of a saturated aqueous solution of ammonium chloride and dichloromethane were added to the reaction solution and then the aqueous layer and the organic layer were separated. The aqueous layer was subjected to extraction with dichloromethane, all of the obtained organic layers were dried over anhydrous magnesium sulfate and filtered, and then, the filtrate was concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: 1,2-dichloroethane:methanol=100:0 to 98:2 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. For the obtained concentration residue, crystallization was performed with dichloromethane/n-hexane, and the deposited solid was collected by filtration and dried under reduced pressure to obtain 88 mg of the title compound (yield: 35%) as a white solid.

Mass spectrum (DUIS, m/z): 455 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.23 & 11.85 (br s, total 1H), 9.75-9.43 (m, 1H), 7.44-7.13 (m, 5H), 5.35 (d, J=4.1 Hz, 1H), 5.05-4.98 (m, 1H), 4.57 (d, J=11.7 Hz, 1H), 4.35 (d, J=11.7 Hz, 1H), 2.65 (dd, J=8.9, 15.1 Hz, 1H), 2.57-2.35 (m, 3H), 2.25-2.09 (m, 2H), 1.89-1.72 (m, 2H), 1.65 (s, 3H), 1.61 (s, 3H), 0.06 (s, 9H).

(R)—N-(3-Hydroxy-1-phenylpropyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. IV-227)

To a solution of 216 mg (0.489 mmol) of ethyl 5-(chlorocarbonyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 3 in 4.5 ml of 1,4-dioxane, 379 mg (2.51 mmol) of (R)-3-amino-3-phenylpropan-1-ol [purchased from Ark Pharm, Inc.] and 0.17 ml (0.99 mmol) of DIPEA were added at room temperature in an argon atmosphere, then applied to a microwave reaction apparatus, and reacted at 100° C. for 1 hour. After standing to cool, 1.0 ml of methanol and 0.5 ml of triethylamine were added, applied to a microwave reaction apparatus, and reacted at 80° C. for 1 hour.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure, and ethyl acetate, water, and a saturated aqueous solution of sodium chloride were added thereto and then the aqueous layer and the organic layer were separated. The organic layer was dried over anhydrous magnesium sulfate and filtered, and then, the filtrate was concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: 1,2-dichloroethane:methanol=99:1 to 96:4 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. For the obtained concentration residue, crystallization was performed with ethyl acetate/diisopropyl ether, and the deposited solid was collected by filtration and dried under reduced pressure to obtain 173 mg of the title compound (yield: 73%) as a white solid.

Mass spectrum (CI, m/z): 484 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.19 & 11.66 (s, total 1H), 9.61-9.47 (m, 1H), 7.39-7.13 (m, 5H), 6.46 & 6.38 (d, J=8.0 Hz, total 1H), 4.92-4.83 (m, 1H), 4.66-4.33 (m, 3H), 3.46-3.34 (m, 2H), 2.50-2.41 (m, 2H), 2.26-2.13 (m, 2H), 2.01-1.72 (m, 4H), 1.65-1.47 (m, 6H), 0.12-0.06 (m, 9H).

(R)—N-(3-Hydroxy-1-phenylpropyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclopropanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. III-226)

To a solution of 468 mg (1.17 mmol) of ethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclopropanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate hydrochloride synthesized in the similar manner as in Reference Example 7 in 10 ml of dehydrated dichloromethane, 0.72 ml (4.1 mmol) of DIPEA was added at room temperature in a nitrogen atmosphere, and then, 235 mg (0.791 mmol) of bis(trichloromethyl)carbonate was added at −78° C. and stirred at the same temperature as above for 3 hours.

After the completion of the reaction, 20 ml of a saturated aqueous solution of sodium bicarbonate was added to the reaction solution and stirred while the temperature was raised to room temperature for a while. The organic layer and the aqueous layer were separated, and then, the aqueous layer was subjected to extraction with dichloromethane twice. All of the obtained organic layers were dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (elution solvent: n-hexane:ethyl acetate=90:10 to 75:25 (V/V)), and a fraction containing ethyl 5-(chlorocarbonyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclopropanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate was concentrated under reduced pressure and dried under reduced pressure to obtain 490 mg of a concentration residue.

To a solution of 113 mg of the obtained concentration residue in 2 ml of dehydrated THF, 0.14 ml (0.80 mmol) of DIPEA and 105 mg (0.692 mmol) of (R)-3-amino-3-phenylpropan-1-ol [purchased from Ark Pharm, Inc.] were added at room temperature in a nitrogen atmosphere and then stirred for 2.5 hours while heated to reflux. Subsequently, 0.10 ml (1.7 mmol) of 2-aminoethanol was added and then stirred for 2 hours while heated to reflux.

After the completion of the reaction, a saturated aqueous solution of sodium bicarbonate was added to the reaction solution, followed by extraction with dichloromethane three times. All of the obtained organic layers were dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. 0.1 ml of acetic acid was added to the obtained concentration residue and then subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=50:50 to 15:85 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was subjected again to silica gel column chromatography (elution solvent: dichloromethane:methanol=99:1 to 95:5 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. For the obtained concentration residue, crystallization was performed with ethyl acetate/n-hexane, and the deposited solid was collected by filtration, washed by sousing with n-hexane, and then dried under reduced pressure to obtain 49 mg of the title compound (yield: 39% [2 steps]) as a white solid.

Mass spectrum (CI, m/z): 470 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.22 & 11.84 (br s, total 1H), 9.91-9.66 (m, 1H), 7.37-7.26 (m, 4H), 7.21-7.14 (m, 1H), 6.50-6.28 (m, 1H), 4.92-4.80 (m, 1H), 4.65-4.52 (m, 1H), 4.49-4.31 (m, 2H), 3.44-3.36 (m, 2H), 2.00-1.77 (m, 2H), 1.59 (br s, 3H), 1.51 (br s, 3H), 1.06-0.93 (m, 2H), 0.81-0.61 (m, 2H), 0.03 (s, 9H).

(R)—N-(4-Hydroxy-1-phenylbutyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. IV-283)

To a solution of 100 mg (0.227 mmol) of ethyl 5-(chlorocarbonyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 3 and 138 mg (0.684 mmol) of (R)-4-amino-4-phenylbutan-1-ol hydrochloride [purchased from NetChem, Inc.] in 2 ml of dehydrated 1,4-dioxane, 0.24 ml (1.4 mmol) of DIPEA was added at room temperature in an argon atmosphere and stirred at 100° C. for 3 hours. Subsequently, 1 ml of triethylamine and 1 ml of ethanol were added to the reaction solution and heated and stirred at 80° C. for 5 hours.

After the completion of the reaction, water was added to the reaction solution, followed by extraction from the mixed solution with ethyl acetate. The obtained organic layer was washed with a saturated aqueous solution of sodium chloride, dried by adding anhydrous sodium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=50:50 to 0:100 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure and dried under reduced pressure to obtain 91.3 mg of the title compound (yield: 81%) as a white solid.

Mass spectrum (CI, m/z): 498 [M+1] +

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.18 & 11.73 (s, total 1H), 9.66-9.40 (m, 1H), 7.38-7.33 (m, 2H), 7.33-7.26 (m, 2H), 7.21-7.13 (m, 1H), 6.43-6.16 (m, 1H), 4.75-4.66 (m, 1H), 4.47 (br s, 2H), 4.38 (t, J=5.2 Hz, 1H), 3.45-3.35 (m, 2H), 2.49-2.42 (m, 2H), 2.25-2.14 (m, 2H), 1.88-1.64 (m, 4H), 1.60 (br s, 3H), 1.55-1.28 (m, 5H), 0.09 (s, 9H).

(R)—N-(5-Hydroxy-1-phenylpentyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. IV-291)

To a solution of 9.50 ml (9.50 mmol) of 1 M lithium aluminum hydride/THF solution in 40 ml of dehydrated THF, a solution of 2.02 g (6.28 mmol) of (R)-ethyl 5-[(tert-butoxycarbonyl)amino]-5-phenylpentanoate [synthesized according to the method described in Tetrahedron Lett., 1998, 39, 5951-5954] in 20 ml of dehydrated THF was added dropwise with stirring at 0° C. in an argon atmosphere and stirred at the same temperature as above for 2 hours.

After the completion of the reaction, 50 ml of THF was added, and then, 0.4 ml of water and 1.6 ml (1.6 mmol) of a 1 N aqueous sodium hydroxide solution were added and stirred at the same temperature as above for 30 minutes. The deposited solid was filtered using a celite filter, and the solid was washed with ethyl acetate. The obtained filtrate was concentrated under reduced pressure and dried under reduced pressure to obtain a concentration residue.

To a solution of 1.68 g of the obtained concentration residue in 20 ml of dichloromethane, 2 ml of trifluoroacetic acid was added at room temperature in an argon atmosphere and stirred at the same temperature as above for 2 hours.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure and dried under reduced pressure to obtain 1.35 g of a concentration residue.

To a solution of 905 mg of the obtained concentration residue in 3 ml of dehydrated THF, 0.60 ml (3.4 mmol) of DIPEA was added with stirring in an argon atmosphere, and then, 205 mg (0.465 mmol) of ethyl 5-(chlorocarbonyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 3 was added at room temperature and stirred at 60° C. for 4 hours. Subsequently, 0.5 ml of triethylamine and 1 ml of methanol were added to the reaction solution, heated and stirred at 60° C. for 3 hours, and subsequently stirred at room temperature for 15 hours.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel chromatography (DIOL silica gel, elution solvent: dichloromethane:methanol=100:0 to 90:10 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure and dried under reduced pressure. The obtained concentration residue was further subjected to silica gel chromatography (DNH silica gel, elution solvent: dichloromethane:methanol=100:0 to 93:7 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure and dried under reduced pressure. The obtained concentration residue was subjected to silica gel chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=70:30 to 0:100 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure and dried under reduced pressure to obtain 131 mg of the title compound (yield: 55%) as a white solid.

Mass spectrum (CI, m/z): 512 [M+1] +

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.18 & 11.64 (br s, total 1H), 9.58-9.47 (m, 1H), 7.38-7.33 (m, 2H), 7.32-7.25 (m, 2H), 7.21-7.14 (m, 1H), 6.38-6.15 (m, 1H), 4.75-4.65 (m, 1H), 4.52-4.38 (m, 2H), 4.33 (t, J=5.2 Hz, 1H), 3.39-3.33 (m, 2H), 2.49-2.42 (m, 2H), 2.26-2.14 (m, 2H), 1.88-1.72 (m, 3H), 1.72-1.30 (m, 10H), 1.27-1.14 (m, 1H), 0.13-0.06 (m, 9H).

(S)—N-(2-Hydroxy-2-methyl-1-phenylpropyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. IV-171)

To a solution of 200 mg (0.454 mmol) of ethyl 5-(chlorocarbonyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 3 in 3 ml of dehydrated THF, 0.16 ml (0.92 mmol) of DIPEA and 385 mg (2.33 mmol) of (S)-1-amino-2-methyl-1-phenylpropan-2-ol [purchased from IS Chemical Technology Ltd.] were added at room temperature in an argon atmosphere and stirred at 60° C. for 4 hours. Subsequently, 1 ml of methanol and 1 ml of triethylamine were added at room temperature and stirred at the same temperature as above for 15 hours.

After the completion of the reaction, water was added to the reaction solution, followed by extraction from the mixed solution with ethyl acetate. The obtained organic layer was washed with a saturated aqueous solution of sodium chloride, dried by adding anhydrous sodium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel chromatography (DIOL silica gel, elution solvent: dichloromethane:methanol=100:0 to 90:10 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure and dried under reduced pressure. The obtained concentration residue was subjected again to silica gel chromatography (DIOL silica gel, elution solvent: dichloromethane:methanol=100:0 to 90:10 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure and dried under reduced pressure to obtain 182 mg of the title compound (yield: 81%) as a white solid.

Mass spectrum (DUIS, m/z): 498 [M+1] +

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.22 & 11.78 (br s, total 1H), 9.74-9.49 (m, 1H), 7.38-7.16 (m, 5H), 5.90-5.74 (m, 1H), 4.85 (s, 1H), 4.65-4.35 (m, 3H), 2.49-2.41 (m, 2H), 2.28-2.15 (m, 2H), 1.91-1.73 (m, 2H), 1.67-1.44 (m, 6H), 1.22 (s, 3H), 0.91 (s, 3H), 0.09 (s, 9H).

(S)—N-(2-Hydroxy-2-methyl-1-phenylpropyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclopropanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. III-170)

To a solution of 468 mg (1.17 mmol) of ethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclopropanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate hydrochloride synthesized in the similar manner as in Reference Example 7 in 10 ml of dehydrated dichloromethane, 0.72 ml (4.1 mmol) of DIPEA was added at room temperature in a nitrogen atmosphere, and then, 235 mg (0.791 mmol) of bis(trichloromethyl)carbonate was added at −78° C. and stirred at the same temperature as above for 3 hours.

After the completion of the reaction, 20 ml of a saturated aqueous solution of sodium bicarbonate was added to the reaction solution and stirred while the temperature was raised to room temperature for a while. The organic layer and the aqueous layer were separated, and then, the aqueous layer was subjected to extraction with dichloromethane twice. All of the obtained organic layers were dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (elution solvent: n-hexane:ethyl acetate=90:10 to 75:25 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure and dried under reduced pressure to obtain 490 mg of a concentration residue.

To a solution of 112 mg of the obtained concentration residue in 2 ml of dehydrated THF, 0.14 ml (0.80 mmol) of DIPEA and 109 mg (0.660 mmol) of (S)-1-amino-2-methyl-1-phenylpropan-2-ol [purchased from IS Chemical Technology Ltd.] were added in this order at room temperature in a nitrogen atmosphere and then stirred for 3 hours while heated to reflux. Subsequently, 0.10 ml (1.7 mmol) of 2-aminoethanol was added and then stirred for 2.5 hours while heated to reflux.

After the completion of the reaction, a saturated aqueous solution of sodium bicarbonate was added to the reaction solution, followed by extraction with dichloromethane three times. All of the obtained organic layers were dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. 0.1 ml of acetic acid was added to the obtained concentration residue and then subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=50:50 to 20:80 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. For the obtained concentration residue, crystallization was performed with ethyl acetate/n-hexane, and the deposited solid was collected by filtration, washed by sousing with n-hexane, and then dried under reduced pressure to obtain 100 mg of the title compound (yield: 77% [2 steps]) as a white solid.

Mass spectrum (CI, m/z): 484 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.24 & 11.90 (br s, total 1H), 10.02-9.68 (m, 1H), 7.38-7.16 (m, 5H), 5.89-5.71 (m, 1H), 4.82 (s, 1H), 4.59 (d, J=8.4 Hz, 1H), 4.56-4.31 (m, 2H), 1.66-1.43 (m, 6H), 1.21 (s, 3H), 1.06-0.97 (m, 2H), 0.91 (s, 3H), 0.81-0.61 (m, 2H), 0.04 (s, 9H).

N-(3-Hydroxy-2,2-dimethyl-1-phenylpropyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. IV-354)

To a solution of 152 mg (0.346 mmol) of ethyl 5-(chlorocarbonyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 3 and 201 mg (1.12 mmol) of 3-amino-2,2-dimethyl-3-phenylpropan-1-ol [synthesized according to the method described in Synthetic Communications 1994, 24 (7), 899-906] in 4 ml of 1,4-dioxane, 0.18 ml (1.0 mmol) of DIPEA was added at room temperature in an argon atmosphere, then applied to a microwave reaction apparatus, and reacted at 100° C. for 1 hour. After standing to cool, the reaction solution was concentrated under reduced pressure, and 4 ml of methanol and 1 ml of triethylamine were added to the obtained concentration residue and stirred at room temperature for 15 hours.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure, the obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: ethyl acetate:methanol=99:1 to 97:3 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was subjected again to silica gel column chromatography (DIOL silica gel, elution solvent: 1,2-dichloroethane:methanol=99:1 to 92:8 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. For the obtained concentration residue, crystallization was performed with dichloromethane/n-hexane, and the deposited solid was collected by filtration and dried under reduced pressure to obtain 55 mg of the title compound (yield: 31%) as a white solid.

Mass spectrum (DUIS, m/z): 512 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.21 & 11.95 (br s, total 1H), 9.89-9.36 (m, 1H), 7.36-7.17 (m, 5H), 6.85 (d, J=8.1 Hz, 1H), 5.50-5.39 (m, 1H), 4.64 (d, J=8.1 Hz, 1H), 4.47-4.28 (m, 2H), 3.30-3.22 (m, 1H), 3.03 (dd, J=4.1, 10.4 Hz, 1H), 2.49-2.40 (m, 2H), 2.28-2.13 (m, 2H), 1.92-1.71 (m, 2H), 1.60 (br s, 3H), 1.53 (s, 3H), 1.06 (s, 3H), 0.64 (s, 3H), 0.09 (s, 9H).

(R)—N-(3-Hydroxy-3-methyl-1-phenylbutyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. IV-299)

To a solution of 132 mg (0.300 mmol) of ethyl 5-(chlorocarbonyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 3 and 155 mg (0.865 mmol) of (R)-4-amino-2-methyl-4-phenylbutan-2-ol synthesized in the similar manner as in Reference Example 23 in 4 ml of 1,4-dioxane, 0.15 ml (0.86 mmol) of DIPEA was added at room temperature in an argon atmosphere and then stirred at 100° C. for 2 hours. After standing to cool, the reaction solution was concentrated under reduced pressure, and 4 ml of methanol and 1 ml of triethylamine were added to the obtained concentration residue and stirred at room temperature for 18 hours.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure, and ethyl acetate, water, and a saturated aqueous solution of sodium chloride were added to the obtained concentration residue and then the aqueous layer and the organic layer were separated. The obtained organic layer was dried over anhydrous magnesium sulfate and filtered, and then, the filtrate was concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: 1,2-dichloroethane:methanol=98:2 to 91:9 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. For the obtained concentration residue, crystallization was performed with dichloromethane/diethyl ether/n-hexane, and the deposited solid was collected by filtration and dried under reduced pressure to obtain 104 mg of the title compound (yield: 68%) as a white solid.

Mass spectrum (DUIS, m/z): 512 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.20 & 11.73 (br s, 1H), 9.66-9.40 (m, 1H), 7.37-7.25 (m, 4H), 7.19-7.13 (m, 1H), 6.54 (d, J=5.3 Hz, 1H), 4.95-4.84 (m, 1H), 4.75-4.57 (m, 1H), 4.45 (br s, 2H), 2.47-2.42 (m, 2H), 2.25-2.14 (m, 2H), 2.02-1.74 (m, 3H), 1.65 (dd, J=3.3, 14.3 Hz, 1H), 1.58 (s, 3H), 1.53 (s, 3H), 1.16 (s, 3H), 1.13 (s, 3H), 0.09 (s, 9H).

(S)—N-(2-Methoxy-1-phenylethyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. IV-123)

To a solution of 201 mg (0.456 mmol) of ethyl 5-(chlorocarbonyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 3 in 4.5 ml of 1,4-dioxane, 0.16 ml (0.91 mmol) of DIPEA and 213 mg (1.41 mmol) of (S)-2-methoxy-1-phenylamine [synthesized according to the method described in J. Chem. Soc., Perkin Transactions 1, 2002, 20, 2237-2242] were added at room temperature, then applied to a microwave reaction apparatus, and reacted at 100° C. for 1 hour. Subsequently, 1 ml of methanol and 0.5 ml of triethylamine were added and then reacted at 80° C. for 1 hour in a microwave reaction apparatus again.

After the completion of the reaction, 8 ml of ethyl acetate, 0.4 ml of water, and 8 ml of a saturated aqueous solution of sodium chloride were added to the reaction solution and then the aqueous layer and the organic layer were separated. The aqueous layer was subjected to extraction with 10 ml of dichloromethane. All of the obtained organic layers were dried over anhydrous magnesium sulfate, then filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: 1,2-dichloroethane:methanol=100:0 to 95:5 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. Diethyl ether was added to the obtained concentration residue and ultrasonicated, and then, the deposited insoluble matter was collected by filtration and dried under reduced pressure to obtain 180 mg of the title compound (yield: 82%) as a white solid.

Mass spectrum (CI, m/z): 484 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.20 & 11.67 (br s, total 1H), 9.68-9.41 (m, 1H), 7.41-7.35 (m, 2H), 7.34-7.27 (m, 2H), 7.25-7.17 (m, 1H), 6.44-6.13 (m, 1H), 5.02-4.92 (m, 1H), 4.57-4.39 (m, 2H), 3.63 (dd, J=7.9, 9.9 Hz, 1H), 3.50 (dd, J=6.0, 9.9 Hz, 1H), 3.26 (s, 3H), 2.49-2.42 (m, 2H), 2.26-2.15 (m, 2H), 1.92-1.73 (m, 2H), 1.60 (br s, 3H), 1.53 (br s, 3H), 0.09 (s, 9H).

(S)—N-[2-(Difluoromethoxy)-1-phenylethyl]-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. IV-131)

To a solution of 210 mg (0.697 mmol) of (S)-2-(difluoromethoxy)-1-phenylethanamine trifluoroacetate synthesized in the similar manner as in Reference Example 25 and 0.425 ml (2.43 mmol) of DIPEA in 3 ml of dehydrated 1,4-dioxane, 107 mg (0.243 mmol) of ethyl 5-(chlorocarbonyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 3 was added at room temperature in an argon atmosphere and heated and stirred at 100° C. for 1 hour. Subsequently, 1 ml of triethylamine and 1 ml of methanol were added to the reaction solution and heated and stirred at 80° C. for 1 hour.

After the completion of the reaction, water was added to the reaction solution, followed by extraction from the mixed solution with ethyl acetate. The obtained organic layer was washed with a saturated aqueous solution of sodium chloride, dried by adding anhydrous sodium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=50:50 to 0:100 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure and dried under reduced pressure to obtain 40.5 mg of the title compound (yield: 32%) as a white solid.

Mass spectrum (CI, m/z): 520 [M+1] +

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.20 (br s, 1H), 10.12-9.41 (m, 1H), 7.43-7.38 (m, 2H), 7.38-7.32 (m, 2H), 7.28-7.23 (m, 1H), 6.70 (t, J=76.0 Hz, 1H), 6.59-6.46 (m, 1H), 5.10-5.01 (m, 1H), 4.52-4.43 (m, 2H), 4.13 (dd, J=8.3, 10.4 Hz, 1H), 4.05-3.99 (m, 1H), 2.48-2.42 (m, 2H), 2.24-2.15 (m, 2H), 1.88-1.75 (m, 2H), 1.60 (s, 3H), 1.53 (s, 3H), 0.09 (s, 9H).

(S)—N-(2-Ethoxy-1-phenylethyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. IV-139)

To a solution of 136 mg (0.308 mmol) of ethyl 5-(chlorocarbonyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 3 and 162 mg (0.979 mmol) of (S)-2-ethoxy-1-phenylethanamine synthesized in the similar manner as in Reference Example 26 in 4 ml of 1,4-dioxane, 0.16 ml (0.92 mmol) of DIPEA was added at room temperature in an argon atmosphere and then stirred at 100° C. for 2 hours. After standing to cool, the reaction solution was concentrated under reduced pressure, and 4 ml of methanol and 1 ml of triethylamine were added to the obtained concentration residue, applied to a microwave reaction apparatus, and reacted at 80° C. for 1 hour.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure, ethyl acetate was added to the obtained concentration residue, then the organic layer obtained by washing with a 10% aqueous potassium dihydrogen phosphate solution, a saturated aqueous solution of sodium bicarbonate, and a saturated aqueous solution of sodium chloride in this order was dried over anhydrous magnesium sulfate and filtered, and then, the filtrate was concentrated under reduced pressure. The obtained residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: 1,2-dichloroethane:methanol=98:2 to 91:9 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. For the obtained concentration residue, crystallization was performed with dichloromethane/diethyl ether/n-hexane, and the deposited solid was collected by filtration. The obtained solid was subjected again to silica gel column chromatography (DIOL silica gel, elution solvent: 1,2-dichloroethane:methanol=100:0 to 93:7 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was subjected again to silica gel column chromatography (DIOL silica gel, elution solvent: 1,2-dichloroethane:ethyl acetate=100:0 to 67:33 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. Diethyl ether and n-hexane were added to the obtained concentration residue, and after ultrasonication, the deposited solid was collected by filtration and dried under reduced pressure to obtain 81 mg of the title compound (yield: 53%) as a white solid.

Mass spectrum (DUIS, m/z): 498 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.20 & 11.71 (br s, total 1H), 9.67-9.47 (m, 1H), 7.41-7.34 (m, 2H), 7.34-7.27 (m, 2H), 7.25-7.17 (m, 1H), 6.38-6.11 (m, 1H), 4.99-4.91 (m, 1H), 4.56-4.38 (m, 2H), 3.65 (dd, J=8.0, 9.9 Hz, 1H), 3.54 (dd, J=6.0, 9.9 Hz, 1H), 3.51-3.41 (m, 2H), 2.49-2.41 (m, 2H), 2.28-2.14 (m, 2H), 1.91-1.71 (m, 2H), 1.61 (br s, 3H), 1.54 (br s, 3H), 1.08 (t, J=7.0 Hz, 3H), 0.09 (s, 9H).

(R)—N-(3-Methoxy-1-phenylpropyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. IV-235)

To a solution of 138 mg (0.314 mmol) of ethyl 5-(chlorocarbonyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 3 and 163 mg (0.987 mmol) of (R)-3-methoxy-1-phenylpropan-1-amine synthesized in the similar manner as in Reference Example 27 in 4 ml of 1,4-dioxane, 0.16 ml (0.92 mmol) of DIPEA was added at room temperature in an argon atmosphere and then stirred at 100° C. for 2 hours. After standing to cool, the reaction solution was concentrated under reduced pressure, and 4 ml of methanol and 1 ml of triethylamine were added to the obtained residue and stirred at room temperature for 18 hours.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure, ethyl acetate was added to the obtained concentration residue, then the organic layer obtained by washing with a 10% aqueous potassium dihydrogen phosphate solution, a saturated aqueous solution of sodium bicarbonate, and a saturated aqueous solution of sodium chloride in this order was dried over anhydrous magnesium sulfate and filtered, and then, the filtrate was concentrated under reduced pressure. The obtained residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: 1,2-dichloroethane:methanol=95:5 to 88:12 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. Diethyl ether and n-hexane were added to the obtained concentration residue and ultrasonicated, and then, the deposited solid was collected by filtration and dried under reduced pressure to obtain 88 mg of the title compound (yield: 56%) as a white solid.

Mass spectrum (DUIS, m/z): 498 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.18 & 11.73 (br s, total 1H), 9.54 (br s, 1H), 7.35-7.28 (m, 4H), 7.22-7.16 (m, 1H), 6.41 (br s, 1H), 4.91-4.79 (m, 1H), 4.53-4.40 (m, 2H), 3.32-3.27 (m, 2H), 3.23 (s, 3H), 2.50-2.42 (m, 2H), 2.26-2.15 (m, 2H), 2.08-1.70 (m, 4H), 1.60 (s, 3H), 1.52 (s, 3H), 0.09 (s, 9H).

Sodium (S)-2-{6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazole-5-carboxamido}-2-phenylacetate (sodium salt of Compound No. IV-403)

To a solution of 98.0 mg (0.171 mmol) of (S)-benzyl 2-{6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazole-5-carboxamido}-2-phenylacetate synthesized in the similar manner as in Example 55 in 15 ml of ethanol, 19.9 mg of palladium/carbon [ASCA2 (trade name), manufactured by N.E. Chemcat Corp., containing 52% water] was added in a nitrogen atmosphere and then, after replacement with a hydrogen atmosphere under reduced pressure, stirred at room temperature for 50 minutes.

After the completion of the reaction, replacement with an argon atmosphere was performed, and the reaction solution was filtered through celite. 14.8 mg (0.176 mmol) of sodium bicarbonate was added to the obtained filtrate and concentrated under reduced pressure. Purified water and diethyl ether were added to the obtained concentration residue and then dried under reduced pressure to obtain 82 mg of the title compound (yield: 95%) as a white solid.

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.41 (br s, 1H), 9.95 (br. s, 1H), 7.38-7.30 (m, 2H), 7.24-7.17 (m, 2H), 7.14-7.08 (m, 1H), 6.42 (d, J=4.6 Hz, 1H), 4.68 (d, J=4.6 Hz, 1H), 4.48 (d, J=11.3 Hz, 1H), 4.45 (d, J=11.3 Hz, 1H), 2.51-2.41 (m, 2H), 2.28-2.14 (m, 2H), 1.90-1.74 (m, 2H), 1.59 (s, 3H), 1.55 (s, 3H), 0.08 (s, 9H).

(R)—N-(2-Hydroxy-1-phenylethyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. IV-115)

To a solution of 127 mg (0.287 mmol) of ethyl 5-(chlorocarbonyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 3 and 203 mg (1.48 mmol) of (R)-2-amino-2-phenylethanol in 3 ml of THF, 0.15 ml (0.86 mmol) of DIPEA was added at room temperature in an argon atmosphere and then stirred at 60° C. for 3 hours.

After the completion of the reaction, ethyl acetate, water, and a saturated aqueous solution of sodium chloride were added to the reaction solution and then the aqueous layer and the organic layer were separated. The obtained organic layer was dried over anhydrous magnesium sulfate and filtered, and then, the filtrate was concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: 1,2-dichloroethane:methanol=100:0 to 98:2 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was subjected again to silica gel column chromatography (elution solvent: ethyl acetate:a mixed solution of 28% aqueous ammonia solution/ethanol [1:5 (V/V)]=98:2 to 95:5 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure and dried under reduced pressure to obtain 82 mg of the title compound (yield: 61%) as a white foam.

Mass spectrum (DUIS, m/z): 470 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.20 & 11.79 (br s, total 1H), 9.73-9.49 (m, 1H), 7.44-7.11 (m, 5H), 6.25-6.00 (m, 1H), 4.95-4.70 (m, 2H), 4.62-4.41 (m, 2H), 3.71-3.52 (m, 2H), 2.48-2.41 (m, 2H), 2.27-2.13 (m, 2H), 1.93-1.73 (m, 2H), 1.71-1.43 (m, 6H), 0.09 (br s, 9H).

N-[1-(2-Fluorophenyl)-2-hydroxyethyl]-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. IV-510)

To a solution of 201 mg (0.456 mmol) of ethyl 5-(chlorocarbonyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 3 in 5 ml of 1,4-dioxane, 0.23 ml (1.4 mmol) of DIPEA and 212 mg (1.37 mmol) of 2-amino-2-(2-fluorophenyl)ethanol [purchased from Amatek Chemical Co., Ltd.] were added at room temperature in an argon atmosphere and then reacted at 100° C. for 1 hour. The reaction solution was concentrated under reduced pressure, and then, 4 ml of methanol and 1 ml of triethylamine were added to the concentration residue and reacted at 65° C. for 4.5 hours and further at 70° C. for 1.5 hours.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure, and the obtained concentration residue was dissolved in 5 ml of ethyl acetate and washed with 10 ml of a 5% aqueous potassium bisulfate solution twice. All of the obtained organic layers were washed with 10 ml of a saturated aqueous solution of sodium bicarbonate, then dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: 1,2-dichloroethane:methanol=100:0 to 98:2 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure and dried under reduced pressure to obtain 131 mg of the title compound (yield: 59%) as a white foam.

Mass spectrum (CI, m/z): 488 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.41-11.66 (m, 1H), 9.94-9.30 (m, 1H), 7.51-7.42 (m, 1H), 7.31-7.06 (m, 3H), 6.19 (br s, 1H), 5.15-5.04 (m, 1H), 4.98 (t, J=6.0 Hz, 1H), 4.54 (br s, 2H), 3.64-3.54 (m, 2H), 2.49-2.42 (m, 2H), 2.26-2.15 (m, 2H), 1.87-1.76 (m, 2H), 1.60 (s, 3H), 1.51 (s, 3H), 0.10 (s, 9H).

(S)—N-[1-(3-Fluorophenyl)-2-hydroxyethyl]-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. IV-519)

To a solution of 201 mg (0.456 mmol) of ethyl 5-(chlorocarbonyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 3 in 5.0 ml of 1,4-dioxane, 0.23 ml (1.4 mmol) of DIPEA and 212 mg (1.37 mmol) of (S)-2-amino-2-(3-fluorophenyl)ethanol [purchased from Amatek Chemical Co., Ltd.] were added at room temperature in an argon atmosphere and then reacted at 100° C. for 1 hour. The reaction solution was concentrated under reduced pressure, and then, 4 ml of methanol and 1 ml of triethylamine were added to the concentration residue and reacted at room temperature for 17 hours.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure, and the obtained concentration residue was dissolved in 5 ml of ethyl acetate, washed with 10 ml of a 5% aqueous potassium dihydrogen phosphate solution twice and 10 ml of a saturated aqueous solution of sodium bicarbonate once, then dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: 1,2-dichloroethane:methanol=100:0 to 98:2 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure and dried under reduced pressure to obtain 128 mg of the title compound (yield: 58%) as a white foam.

Mass spectrum (CI, m/z): 488 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.35-11.70 (m, 1H), 9.84-9.41 (m, 1H), 7.38-7.29 (m, 1H), 7.21-7.15 (m, 2H), 7.05-6.98 (m, 1H), 6.21 (br s, 1H), 4.92 (t, J=5.8 Hz, 1H), 4.83-4.74 (m, 1H), 4.58-4.45 (m, 2H), 3.67-3.55 (m, 2H), 2.49-2.42 (m, 2H), 2.26-2.15 (m, 2H), 1.89-1.73 (m, 2H), 1.60 (s, 3H), 1.53 (s, 3H), 0.09 (s, 9H).

(S)—N-[1-(4-Fluorophenyl)-2-hydroxyethyl]-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. IV-527)

To a solution of 201 mg (0.456 mmol) of ethyl 5-(chlorocarbonyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 3 in 5.0 ml of 1,4-dioxane, 0.23 ml (1.4 mmol) of DIPEA and 212 mg (1.37 mmol) of (S)-2-amino-2-(4-fluorophenyl)ethanol [purchased from Amatek Chemical Co., Ltd.] were added at room temperature in an argon atmosphere and then reacted at 100° C. for 1 hour. The reaction solution was concentrated under reduced pressure, and then, 4 ml of methanol and 1 ml of triethylamine were added to the concentration residue and reacted at room temperature for 15 hours.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure, and the obtained concentration residue was dissolved in 5 ml of ethyl acetate, washed with 10 ml of a 5% aqueous potassium dihydrogen phosphate solution twice and 10 ml of a saturated aqueous solution of sodium bicarbonate once, then dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: 1,2-dichloroethane:methanol=100:0 to 98:2 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was subjected again to silica gel column chromatography (DIOL silica gel, elution solvent: 1,2-dichloroethane:methanol=100:0 to 98:2 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure and dried under reduced pressure to obtain 139 mg of the title compound (yield: 63%) as a pale yellow foam.

Mass spectrum (CI, m/z): 488 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.20 & 11.71 (br s, total 1H), 9.75-9.43 (m, 1H), 7.42-7.33 (m, 2H), 7.15-7.06 (m, 2H), 6.28-6.02 (m, 1H), 4.89 (t, J=5.8 Hz, 1H), 4.81-4.72 (m, 1H), 4.51 (br s, 2H), 3.66-3.53 (m, 2H), 2.49-2.42 (m, 2H), 2.26-2.15 (m, 2H), 1.90-1.74 (m, 2H), 1.60 (br s, 3H), 1.53 (br s, 3H), 0.09 (s, 9H).

N-[2-Hydroxy-1-(pyridin-2-yl)ethyl]-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. IV-534)

To a solution of 152 mg (0.344 mmol) of ethyl 5-(chlorocarbonyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 3 and 223 mg (1.06 mmol) of 2-amino-2-(pyridin-2-yl)ethanol dihydrochloride [purchased from J&W PharmLab, LLC] in 4 ml of 1,4-dioxane, 0.60 ml (3.4 mmol) of DIPEA was added at room temperature in an argon atmosphere, then applied to a microwave reaction apparatus, and reacted at 100° C. for 1 hour.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure, and a saturated aqueous solution of sodium bicarbonate was added to the concentration residue, followed by extraction with dichloromethane. The obtained organic layer was dried over anhydrous sodium sulfate and filtered, and then, the filtrate was concentrated under reduced pressure. The obtained residue was subjected to silica gel column chromatography (DNH silica gel, elution solvent: 1,2-dichloroethane:methanol=100:0 to 93:7 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained residue was subjected again to silica gel column chromatography (DIOL silica gel, elution solvent: ethyl acetate:methanol=100:0 to 78:22 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure and dried under reduced pressure to obtain 78 mg of the title compound (yield: 48%) as a white foam.

Mass spectrum (DUIS, m/z): 469 [M−1] − .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.22 & 11.78 (br s, total 1H), 9.79-9.45 (m, 1H), 8.54-8.49 (m, 1H), 7.74 (dt, J=1.7, 7.7 Hz, 1H), 7.42-7.36 (m, 1H), 7.28-7.21 (m, 1H), 6.19-6.00 (m, 1H), 4.92-4.82 (m, 2H), 4.62-4.43 (m, 2H), 3.76-3.65 (m, 2H), 2.49-2.42 (m, 2H), 2.27-2.15 (m, 2H), 1.92-1.72 (m, 2H), 1.68-1.50 (m, 6H), 0.10 (s, 9H).

N-[2-Hydroxy-1-(pyridin-3-yl)ethyl]-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. IV-542)

To a solution of 150 mg (0.341 mmol) of ethyl 5-(chlorocarbonyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 3 and 218 mg (1.03 mmol) of 2-amino-2-(pyridin-3-yl)ethanol dihydrochloride [purchased from J&W PharmLab, LLC] in 4 ml of 1,4-dioxane, 0.60 ml (3.4 mmol) of DIPEA was added at room temperature in an argon atmosphere and then stirred at 100° C. for 1 hour.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure, and a saturated aqueous solution of sodium bicarbonate was added to the concentration residue, followed by extraction with dichloromethane. The obtained organic layer was dried over anhydrous magnesium sulfate and filtered, and then, the filtrate was concentrated under reduced pressure. 4 ml of methanol and 1 ml of triethylamine were added to the obtained concentration residue, applied to a microwave reaction apparatus, and reacted at 80° C. for 1 hour.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure, the obtained concentration residue was subjected to silica gel column chromatography (DNH silica gel, elution solvent: 1,2-dichloroethane:methanol=95:5 to 88:12 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained residue was subjected again to silica gel column chromatography (DNH silica gel, elution solvent: ethyl acetate:methanol=96:4 to 70:30 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained residue was subjected again to silica gel column chromatography (DIOL silica gel, elution solvent: ethyl acetate:methanol=99:1 to 73:27 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure and dried under reduced pressure to obtain 27 mg of the title compound (yield: 17%) as a white foam.

Mass spectrum (DUIS, m/z): 471 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.20 & 11.77 (br s, total 1H), 9.75-9.47 (m, 1H), 8.54 (d, J=2.0 Hz, 1H), 8.41 (dd, J=2.0, 4.7 Hz, 1H), 7.75 (ddd, J=2.0, 2.0, 7.6 Hz, 1H), 7.32 (dd, J=4.7, 7.6 Hz, 1H), 6.39-6.13 (m, 1H), 4.97 (t, J=5.8 Hz, 1H), 4.84-4.76 (m, 1H), 4.61-4.42 (m, 2H), 3.71-3.59 (m, 2H), 2.49-2.42 (m, 2H), 2.27-2.14 (m, 2H), 1.89-1.72 (m, 2H), 1.60 (br s, 3H), 1.52 (br s, 3H), 0.09 (s, 9H).

N-[1-(Benzo[d][1,3]dioxol-4-yl)-2-hydroxyethyl]-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. IV-502)

To a solution of 240 mg (0.815 mmol) of 1-(benzo[d][1,3]dioxol-4-yl)-2-[(tert-butyldimethylsilyl)oxy]ethanamin e synthesized in the similar manner as in Reference Example 32 in 10 ml of dichloromethane, 1 ml (4 mmol) of 4 N hydrogen chloride/1,4-dioxane solution was added at room temperature and stirred at room temperature for 2 hours. The reaction solution was concentrated under reduced pressure, and 3 ml of THF, 0.210 ml (1.24 mmol) of DIPEA, and 93.0 mg (0.211 mmol) of ethyl 5-(chlorocarbonyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 3 were added to the obtained residue at room temperature and stirred at 60° C. for 8 hours.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure, and ethyl acetate, a saturated aqueous solution of sodium chloride, and water were added thereto and then the aqueous layer and the organic layer were separated. The obtained organic layer was dried over anhydrous magnesium sulfate, filtered, and then concentrated under reduced pressure. 2 ml of methanol and 2 ml of triethylamine were added to the obtained concentration residue, applied to a microwave reaction apparatus, and reacted at 80° C. for 30 minutes.

After the completion of the reaction, the concentration residue obtained by concentration under reduced pressure was subjected to silica gel column chromatography (elution solvent: ethyl acetate:a mixed solution of 28% aqueous ammonia solution/ethanol [1:5 (V/V)]=98:2 to 95:5 (V/V)), and a fraction containing N-{1-(benzo[d][1,3]dioxol-4-yl)-2-[(tert-butyldimethylsilyl)oxy]ethyl}-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide was concentrated under reduced pressure to obtain a concentration residue.

To a solution of 119 mg (0.190 mmol) of the obtained concentration residue in 3.5 ml of dehydrated dichloromethane, 0.18 ml (1.0 mmol) of trimethylsilyl trifluoromethanesulfonate was added at 0° C. and stirred at the same temperature as above for 5 minutes, and then, 0.17 ml (1.5 mmol) of 2,6-lutidine and 0.18 ml (1.0 mmol) of trimethylsilyl trifluoromethanesulfonate were added at 0° C. and stirred at the same temperature as above for 5 minutes. Subsequently, 1 ml of methanol and 0.17 ml (1.5 mmol) of 2,6-lutidine were added, and then, the reaction solution was concentrated under reduced pressure. To a solution of the obtained concentration residue in 1 ml of dehydrated dichloromethane, 0.18 ml (1.0 mmol) of trimethylsilyl trifluoromethanesulfonate was added at 0° C. and stirred at the same temperature as above for 5 minutes, and then, 1.0 ml of dehydrated acetonitrile was added at 0° C. and stirred at the same temperature as above for 10 minutes.

After the completion of the reaction, 1 ml of methanol and 0.17 ml (1.5 mmol) of 2,6-lutidine were added to the reaction solution and then concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (elution solvent: ethyl acetate:a mixed solution of 28% aqueous ammonia solution/ethanol [1:5 (V/V)]=98:2 to 95:5 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was subjected again to silica gel column chromatography (DIOL silica gel, elution solvent: ethyl acetate:methanol=100:0 to 95:5 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure and dried under reduced pressure to obtain 52 mg of the title compound (yield: 48%) as a white solid.

Mass spectrum (DUIS, m/z): 514 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.21 & 11.72 (br s, total 1H), 9.69-9.50 (m, 1H), 6.89-6.83 (m, 1H), 6.81-6.76 (m, 2H), 6.12-5.94 (m, 3H), 4.96-4.90 (m, 2H), 4.59-4.43 (m, 2H), 3.62-3.56 (m, 2H), 2.49-2.42 (m, 2H), 2.26-2.15 (m, 2H), 1.90-1.74 (m, 2H), 1.60 (br s, 3H), 1.54 (br s, 3H), 0.10 (s, 9H).

(S)—N-(1-Cyclohexyl-2-hydroxyethyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. IV-495)

To a solution of 326 mg (0.739 mmol) of ethyl 5-(chlorocarbonyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 3 in 4 ml of dehydrated THF, 0.33 ml (1.9 mmol) of DIPEA and 304 mg (2.12 mmol) of (S)-2-amino-2-cyclohexylethanol [synthesized according to the method described in Bioorg. Med. Chem. Lett., 2009, 19, 926-929] were added at room temperature in a nitrogen atmosphere and then stirred for 1.5 hours while heated to reflux. Subsequently, 0.90 ml (6.5 mmol) of triethylamine and 0.90 ml (22 mmol) of methanol were added to the reaction solution and then stirred for 1.5 hours while heated to reflux.

After the completion of the reaction, water was added to the reaction solution, followed by extraction with dichloromethane three times. All of the obtained organic layers were dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. 85 μl of acetic acid was added to the obtained concentration residue and then subjected to silica gel column chromatography (DIOL silica gel, elution solvent: dichloromethane:methanol=100:0 to 97:3 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. For the obtained concentration residue, crystallization was performed with dichloromethane/n-hexane, and the deposited solid was collected by filtration, washed by sousing with n-hexane, and then dried under reduced pressure to obtain 295 mg of the title compound (yield: 84%) as a white solid.

Mass spectrum (CI, m/z): 476 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.20 & 11.71 (br s, total 1H), 9.70-9.44 (m, 1H), 5.46-5.15 (m, 1H), 4.54 (t, J=5.0 Hz, 1H), 4.49-4.21 (m, 2H), 3.53-3.40 (m, 3H), 2.48-2.40 (m, 2H), 2.27-2.10 (m, 2H), 1.88-1.45 (m, 14H), 1.28-1.03 (m, 3H), 1.03-0.83 (m, 2H), 0.08 (s, 9H).

(S)—N-(1-Hydroxy-3-methylbutan-2-yl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. IV-475)

To a solution of 201 mg (0.456 mmol) of ethyl 5-(chlorocarbonyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 3 in 4.5 ml of 1,4-dioxane, 235 mg (2.27 mmol) of (S)-2-amino-3-methylbutan-1-ol and 0.16 ml (0.91 mmol) of DIPEA were added at room temperature in a nitrogen atmosphere and then stirred at 100° C. for 1 hour.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure, and ethyl acetate, water, and a saturated aqueous solution of sodium chloride were added to the concentration residue and then the aqueous layer and the organic layer were separated. The aqueous layer was subjected to extraction with ethyl acetate, all of the obtained organic layers were dried over anhydrous magnesium sulfate and filtered, and then, the filtrate was concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: 1,2-dichloroethane:methanol=99:1 to 96:4 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. Acetone was added to the obtained concentration residue and then ultrasonicated, and the deposited solid was collected by filtration and dried under reduced pressure to obtain 129 mg of the title compound (yield: 65%) as a white solid.

Mass spectrum (CI, m/z): 436 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.20 & 11.67 (br s, total 1H), 9.60-9.48 (m, 1H), 5.45-5.20 (m, 1H), 4.62-4.24 (m, 3H), 3.52-3.39 (m, 3H), 2.49-2.41 (m, 2H), 2.24-2.13 (m, 2H), 1.91-1.73 (m, 3H), 1.60 (br s, 6H), 0.92-0.82 (m, 6H), 0.08 (s, 9H).

(S)—N-(1-Hydroxypropan-2-yl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. IV-455)

To a solution of 200 mg (0.454 mmol) of ethyl 5-(chlorocarbonyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 3 in 4.5 ml of 1,4-dioxane, 170 mg (2.26 mmol) of (S)-2-aminopropan-1-ol and 0.16 ml (0.91 mmol) of DIPEA were added at room temperature, then applied to a microwave reaction apparatus, and reacted at 100° C. for 1 hour.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure, and ethyl acetate, water, and a saturated aqueous solution of sodium chloride were added to the concentration residue and then the aqueous layer and the organic layer were separated. The aqueous layer was subjected to extraction with ethyl acetate, all of the obtained organic layers were dried over anhydrous magnesium sulfate and filtered, and then, the filtrate was concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: 1,2-dichloroethane:methanol=99:1 to 95:5 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. Ethyl acetate was added to the obtained concentration residue and ultrasonicated, and the deposited solid was collected by filtration and dried under reduced pressure to obtain 145 mg of the title compound (yield: 78%) as a white solid.

Mass spectrum (CI, m/z): 408 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.18 & 11.64 (br s, total 1H), 9.52 (s, 1H), 5.70-5.32 (m, 1H), 4.65 (t, J=5.6 Hz, 1H), 4.44-4.28 (m, 2H), 3.77-3.64 (m, 1H), 3.41-3.34 (m, 1H), 3.30-3.23 (m, 1H), 2.49-2.40 (m, 2H), 2.24-2.13 (m, 2H), 1.88-1.72 (m, 2H), 1.60 (s, 6H), 1.05 (d, J=6.7 Hz, 3H), 0.08 (s, 9H).

N-(2-Hydroxyethyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. IV-438)

To a solution of 200 mg (0.454 mmol) of ethyl 5-(chlorocarbonyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 3 in 3 ml of dehydrated THF, 0.16 ml (0.92 mmol) of DIPEA and 0.14 ml (2.3 mmol) of 2-aminoethanol were added at room temperature in an argon atmosphere and stirred at 60° C. for 3 hours.

After the completion of the reaction, water was added to the reaction solution, followed by extraction from the mixed solution with ethyl acetate. The obtained organic layer was washed with a saturated aqueous solution of sodium chloride, then dried by adding anhydrous sodium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=90:10 to 50:50 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure and dried under reduced pressure to obtain 135 mg of the title compound (yield: 76%) as a white solid.

Mass spectrum (DUIS, m/z): 394 [M+1] +

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.19 & 11.60 (br s, total 1H), 9.54 (s, 1H), 6.05-5.85 (m, 1H), 4.66 (t, J=5.5 Hz, 1H), 4.42-4.28 (m, 2H), 3.45-3.36 (m 2H), 3.17-3.02 (m, 2H), 2.48-2.39 (m, 2H), 2.25-2.12 (m, 2H), 1.91-1.71 (m, 2H), 1.67-1.52 (m, 6H), 0.08 (s, 9H).

N-(2-Hydroxy-2-phenylethyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. IV-450)

To a solution of 100 mg (0.227 mmol) of ethyl 5-(chlorocarbonyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 3 in 2 ml of dehydrated 1,4-dioxane, 0.20 ml (1.1 mmol) of DIPEA and 160 mg (1.17 mmol) of 2-amino-1-phenylethanol were added at room temperature in an argon atmosphere and stirred at the same temperature as above for 1 hour.

After the completion of the reaction, water was added to the reaction solution, followed by extraction from the mixed solution with ethyl acetate. The obtained organic layer was washed with a saturated aqueous solution of sodium chloride, then dried by adding anhydrous sodium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=50:50 to 0:100 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure and dried under reduced pressure to obtain 82.0 mg of the title compound (yield: 77%) as a white solid.

Mass spectrum (CI, m/z): 470 [M+1] +

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.38-11.74 (m, 1H), 9.59 (br s, 1H), 7.36-7.29 (m, 4H), 7.26-7.20 (m, 1H), 6.14-5.98 (m, 1H), 5.58 (d, J=4.0 Hz, 1H), 4.70-4.62 (m, 1H), 4.42-4.28 (m, 2H), 3.29-3.23 (m, 1H), 3.10 (ddd, J=4.8, 8.0, 13.2 Hz, 1H), 2.48-2.40 (m, 2H), 2.23-2.14 (m, 2H), 1.88-1.74 (m, 2H), 1.60 (s, 6H), 0.08 (s, 9H).

N-(2-Hydroxypropyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. IV-442)

To a solution of 100 mg (0.227 mmol) of ethyl 5-(chlorocarbonyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 3 and 85 μl (1.1 mmol) of 1-amino-2-propanol in 2 ml of dehydrated 1,4-dioxane, 0.20 ml (1.1 mmol) of DIPEA was added at room temperature in an argon atmosphere and stirred at the same temperature as above for 1.5 hours.

After the completion of the reaction, water was added to the reaction solution, followed by extraction from the mixed solution with ethyl acetate. The obtained organic layer was washed with a saturated aqueous solution of sodium chloride, then dried by adding anhydrous sodium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=50:50 to 0:100 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure and dried under reduced pressure to obtain 61.1 mg of the title compound (yield: 66%) as a white solid.

Mass spectrum (CI, m/z): 408 [M+1] +

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.19 & 11.78 (br s, total 1H), 9.71-9.46 (m, 1H), 6.05-5.78 (m, 1H), 4.76 (d, J=4.4 Hz, 1H), 4.38 (br s, 2H), 3.71-3.61 (m, 1H), 3.09-2.99 (m, 1H), 2.97-2.88 (m, 1H), 2.49-2.39 (m, 2H), 2.25-2.13 (m, 2H), 1.88-1.71 (m, 2H), 1.60 (br s, 6H), 1.01 (d, J=6.3 Hz, 3H), 0.08 (s, 9H).

N-[(2S)-1-Hydroxy-3-methyl-1-phenylbutan-2-yl]-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. IV-487)

To a solution of 1.25 g (6.21 mmol) of (S)-tert-butyl (3-methyl-1-oxobutan-2-yl)carbamate [synthesized according to the method described in J. Am. Chem. Soc., 2004, 126, 11440-11441] in 15 ml of dehydrated THF, 6.60 ml (6.60 mmol) of 1 M phenyl magnesium bromide/THF solution was added dropwise at an internal temperature of 15° C. or lower in an argon atmosphere and, after the completion of the dropwise addition, stirred at room temperature for 1.5 hours.

After the completion of the reaction, the reaction solution was cooled in ice water, and 20 ml of a saturated aqueous solution of ammonium chloride was added and stirred at room temperature. Ethyl acetate and a saturated aqueous solution of sodium chloride were further added thereto and then the aqueous layer and the organic layer were separated. The obtained organic layer was dried over anhydrous magnesium sulfate and filtered, and then, the filtrate was concentrated under reduced pressure. The obtained residue was subjected to silica gel column chromatography (elution solvent: n-hexane:ethyl acetate=90:10 to 70:30 (V/V)), and a fraction containing tert-butyl [(2 S)-1-hydroxy-3-methyl-1-phenylbutan-2-yl]carbamate was concentrated under reduced pressure to obtain a concentration residue.

To a solution of 0.90 g of the obtained concentration residue in 10 ml of dichloromethane, 1.2 ml (10 mmol) of 2,6-lutidine and 1.8 ml (10 mmol) of trimethylsilyl trifluoromethanesulfonate were added dropwise at 0° C. in a nitrogen atmosphere and stirred at the same temperature as above for 2 hours.

After the completion of the reaction, 50 ml of a saturated aqueous solution of sodium bicarbonate was added thereto, stirred, and then the aqueous layer and the organic layer were separated. The aqueous layer was subjected to extraction with dichloromethane, all of the obtained organic layers were dried over anhydrous sodium sulfate and filtered, and then, the filtrate was concentrated under reduced pressure. The operation of adding toluene to the obtained concentration residue and concentrating the resultant under reduced pressure was repeated several times. The obtained concentration residue was subjected to silica gel column chromatography (DNH silica gel, elution solvent: 1,2-dichloroethane:methanol=100:0 to 95:5 (V/V)), and a fraction containing (2S)-2-amino-3-methyl-1-phenylbutan-1-ol was concentrated under reduced pressure. The obtained concentration residue was subjected again to silica gel column chromatography (DIOL silica gel, elution solvent: 1,2-dichloroethane:methanol=100:0 to 95:5 (V/V)), and a fraction containing (2 S)-2-amino-3-methyl-1-phenylbutan-1-ol was concentrated under reduced pressure to obtain a concentration residue.

To a solution of 111 mg (0.251 mmol) of ethyl 5-(chlorocarbonyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 3 in 4.0 ml of 1,4-dioxane, 97 mg of the concentration residue of (2S)-2-amino-3-methyl-1-phenylbutan-1-ol described above and 0.11 ml (0.63 mmol) of DIPEA were added at room temperature, then applied to a microwave reaction apparatus, and reacted at 100° C. for 1 hour. After the reaction, the reaction solution was concentrated under reduced pressure, and 4 ml of methanol and 1 ml of triethylamine were added to the obtained concentration residue, applied to a microwave reaction apparatus, and reacted at 80° C. for 1 hour.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure, the obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: 1,2-dichloroethane:methanol=100:0 to 95:5 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. Diethyl ether and n-hexane were added to the obtained concentration residue and ultrasonicated, and the deposited solid was collected by filtration. The obtained solid was subjected again to silica gel column chromatography (DIOL silica gel, elution solvent: 1,2-dichloroethane:methanol=100:0 to 95:5 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. For the obtained concentration residue, crystallization was performed with acetone/n-heptane, and the deposited solid was collected by filtration. The obtained solid was subjected again to silica gel column chromatography (elution solvent: hexane:ethyl acetate=38:62 to 17:83 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. n-Hexane was added to the obtained concentration residue, and after ultrasonication, the deposited solid was collected by filtration and dried under reduced pressure to obtain 55 mg of the title compound (yield: 42%) as a white solid.

Mass spectrum (CI, m/z): 512 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.15 & 11.74 (br s, total 1H), 9.85-9.20 (m, 1H), 7.33-7.19 (m, 4H), 7.17-7.10 (m, 1H), 5.68 (d, J=5.8 Hz, 1H), 5.32-5.16 (m, 1H), 4.82 (dd, J=2.6, 5.8 Hz, 1H), 4.37-4.23 (m, 2H), 3.52 (ddd, J=2.6, 8.7, 8.7 Hz, 1H), 2.49-2.39 (m, 2H), 2.26-2.13 (m, 2H), 2.00-1.72 (m, 3H), 1.52 (br s, 3H), 1.31 (br s, 3H), 1.03 (d, J=6.7 Hz, 3H), 0.90 (d, J=6.7 Hz, 3H), 0.09 (s, 9H).

N-(4-Hydroxy-1-phenyl-2-butyn-1-yl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. IV-378)

To a solution of 106 mg (0.240 mmol) of ethyl 5-(chlorocarbonyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 3 in 3 ml of dehydrated 1,4-dioxane, 0.24 ml (1.4 mmol) of DIPEA and 146 mg (0.739 mmol) of 4-amino-4-phenyl-2-butyn-1-ol hydrochloride synthesized in the similar manner as in Reference Example 33 were added in an argon atmosphere and stirred at 100° C. for 2 hours. Subsequently, 1 ml of triethylamine and 1 ml of methanol were added to the reaction solution and stirred at 80° C. for 1 hour.

After the completion of the reaction, water was added to the reaction solution, followed by extraction from the mixed solution with ethyl acetate. The obtained organic layer was washed with a saturated aqueous solution of sodium chloride, dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel chromatography (DIOL column, elution solvent: dichloromethane:methanol=100:0 to 90:10 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was subjected again to silica gel chromatography (elution solvent: dichloromethane:methanol=100:0 to 90:10 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure and dried under reduced pressure to obtain 79.6 mg of the title compound (yield: 67%) as a light brown solid.

Mass spectrum (CI, m/z): 494 [M+1] +

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.21 & 11.70 (br s, total 1H), 9.54 (br s, 1H), 7.53-7.47 (m, 2H), 7.38-7.32 (m, 2H), 7.29-7.23 (m, 1H), 7.20-6.97 (m, 1H), 5.89-5.84 (m, 1H), 5.20 (t, J=5.9 Hz, 1H), 4.45 (br s, 2H), 4.15 (dd, J=1.9, 5.9 Hz, 2H), 2.48-2.40 (m, 2H), 2.24-2.12 (m, 2H), 1.87-1.73 (m, 2H), 1.63 (s, 3H), 1.59 (s, 3H), 0.08 (s, 9H).

(S)-2-{6,6-Dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazole-5-carboxamido}-2-phenylethyl acetate (Compound No. V-1442)

To a solution of 360 mg (0.816 mmol) of ethyl 5-(chlorocarbonyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 3 in 10 ml of THF, 883 mg (4.09 mmol) of (S)-2-amino-2-phenylethyl acetate hydrochloride synthesized in the similar manner as in Reference Example 35 and 2.0 ml (12 mmol) of DIPEA were added at room temperature, applied to a microwave reaction apparatus, and reacted at 100° C. for 2 hours. Subsequently, 1.1 ml (27 mmol) of methanol was added, then applied to a microwave reaction apparatus, and reacted at 80° C. for 1 hour. 2.0 ml (49 mmol) of methanol and 1.0 ml (7.2 mmol) of triethylamine were further added, then applied to a microwave reaction apparatus, and reacted at 80° C. for 1 hour.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure, and 15 ml of ethyl acetate and 15 ml of a saturated aqueous solution of sodium chloride were added to the obtained concentration residue and then the aqueous layer and the organic layer were separated. The aqueous layer was subjected to extraction with 15 ml of dichloromethane. All of the obtained organic layers were dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: 1,2-dichloroethane:methanol=100:0 to 90:10 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. Ethyl acetate and diethyl ether were added in small amounts to the obtained concentration residue, then ultrasonicated, cooled in ice water, and then filtered. The obtained solid was subjected again to silica gel column chromatography (DIOL silica gel, elution solvent: ethyl acetate:methanol=100:0 to 99:1 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. Ethyl acetate and diethyl ether were added in small amounts to the obtained concentration residue, then ultrasonicated, cooled in ice water, and then filtered to obtain white solid A. The filtrate was concentrated under reduced pressure, the obtained concentration residue was subjected to silica gel column chromatography (elution solvent: ethyl acetate:methanol=100:0 to 99:1 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. Ethyl acetate and diethyl ether were added in small amounts to the obtained concentration residue, then ultrasonicated, cooled in ice water, and then filtered to obtain white solid B. The white solids A and B were dissolved in ethyl acetate, then diethyl ether was added, and the deposited solid was filtered and dried under reduced pressure to obtain 142 mg of the title compound (yield: 34%) as a white solid.

Mass spectrum (DUIS, m/z): 512 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.21 & 11.71 (br s, total 1H), 9.76-9.33 (m, 1H), 7.43-7.37 (m, 2H), 7.37-7.31 (m, 2H), 7.28-7.22 (m, 1H), 6.65-6.38 (m, 1H), 5.12-5.03 (m, 1H), 4.49 (br s, 2H), 4.30-4.19 (m, 2H), 2.49-2.41 (m, 2H), 2.25-2.14 (m, 2H), 1.98 (s, 3H), 1.89-1.74 (m, 2H), 1.61 (br s, 3H), 1.53 (br s, 3H), 0.09 (s, 9H).

(S)-2-{6,6-Dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazole-5-carboxamido}-2-phenylethyl propionate (Compound No. V-1446)

To a solution of 200 mg (0.369 mmol) of (S)-ethyl 5-[(2-hydroxy-1-phenylethyl)carbamoyl]-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 38 and 0.10 ml (0.74 mmol) of triethylamine in 3 ml of dehydrated dichloromethane, 0.071 ml (0.55 mmol) of propionic anhydride and 9.7 mg (0.079 mmol) of 4-dimethylaminopyridine were added in this order at room temperature in an argon atmosphere and then reacted at room temperature for 5 hours. Subsequently, 1 ml of methanol and 0.5 ml of triethylamine were added and reacted at room temperature for 2 hours.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure, and 10 ml of ethyl acetate, 0.5 ml of water, and 10 ml of a saturated aqueous solution of sodium chloride were added to the obtained concentration residue, and then the aqueous layer and the organic layer were separated. The aqueous layer was subjected to extraction with 10 ml of dichloromethane twice, and all of the obtained organic layers were dried over anhydrous magnesium sulfate, then filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: 1,2-dichloroethane:methanol=100:0 to 95:5 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. Diethyl ether was added to the obtained concentration residue, and after ultrasonication, insoluble matter was filtered and dried under reduced pressure to obtain 138 mg of the title compound (yield: 71%) as a white solid.

Mass spectrum (CI, m/z): 526 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.20 & 11.66 (br s, total 1H), 9.70-9.39 (m, 1H), 7.45-7.30 (m, 4H), 7.28-7.21 (m, 1H), 6.64-6.39 (m, 1H), 5.16-5.03 (m, 1H), 4.57-4.39 (m, 2H), 4.32-4.19 (m, 2H), 2.49-2.41 (m, 2H), 2.27 (q, J=7.5 Hz, 2H), 2.24-2.14 (m, 2H), 1.91-1.72 (m, 2H), 1.67-1.47 (m, 6H), 0.99 (t, J=7.5 Hz, 3H), 0.09 (s, 9H).

(S)-2-{6,6-Dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazole-5-carboxamido}-2-phenylethyl butanoate (Compound No. V-1450)

To a solution of 250 mg (0.461 mmol) of a mixture of (S)-ethyl 5-[(2-hydroxy-1-phenylethyl)carbamoyl]-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-1(4H)-carboxylate synthesized in the similar manner as in Reference Example 38 and (S)-ethyl 5-[(2-hydroxy-1-phenylethyl)carbamoyl]-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate and 0.10 ml (0.74 mmol) of triethylamine in 4.5 ml of 1,4-dioxane, 0.09 ml (0.6 mmol) of butyric anhydride and 9.0 mg (0.074 mmol) of 4-dimethylaminopyridine were added in this order at room temperature in an argon atmosphere and then reacted at 100° C. for 1.5 hours. Subsequently, 1.5 ml (37 mmol) of methanol and 0.75 ml (5.4 mmol) of triethylamine were added, applied to a microwave reaction apparatus, and reacted at 80° C. for 2 hours.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure, and 8 ml of ethyl acetate, 0.4 ml of water, and 8 ml of a saturated aqueous solution of sodium chloride were added to the obtained concentration residue, and then the aqueous layer and the organic layer were separated. The aqueous layer was subjected to extraction with 10 ml of dichloromethane twice, and all of the obtained organic layers were dried over anhydrous magnesium sulfate, then filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: 1,2-dichloroethane:methanol=100:0 to 95:5 (V/V)), a fraction containing the compound of interest was concentrated under reduced pressure, then the obtained concentration residue was subjected again to silica gel column chromatography (DIOL silica gel, elution solvent: 1,2-dichloroethane:ethyl acetate=100:0 to 51:49 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. Water was added to the concentration residue, and after ultrasonication, insoluble matter was filtered and dried under reduced pressure to obtain 80 mg of the title compound (yield: 32%) as a white solid.

Mass spectrum (CI, m/z): 540 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.20 & 11.65 (br s, total 1H), 9.69-9.40 (m, 1H), 7.45-7.37 (m, 2H), 7.37-7.29 (m, 2H), 7.28-7.21 (m, 1H), 6.64-6.39 (m, 1H), 5.15-5.04 (m, 1H), 4.57-4.38 (m, 2H), 4.31-4.20 (m, 2H), 2.49-2.41 (m, 2H), 2.28-2.14 (m, 4H), 1.92-1.73 (m, 2H), 1.64-1.44 (m, 8H), 0.83 (t, J=7.4 Hz, 3H), 0.09 (s, 9H).

(S)-2-{6,6-Dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazole-5-carboxamido}-2-phenylethyl pentanoate (Compound No. V-1458)

To a solution of 200 mg (0.369 mmol) of (S)-ethyl 5-[(2-hydroxy-1-phenylethyl)carbamoyl]-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 38 and 0.10 ml (0.74 mmol) of triethylamine in 3 ml of 1,4-dioxane, 0.09 ml (0.5 mmol) of valeric anhydride and 9.0 mg (0.074 mmol) of 4-dimethylaminopyridine were added at room temperature in an argon atmosphere and then reacted at 100° C. for 1 hour. Subsequently, 1 ml of methanol and 0.5 ml of triethylamine were added, applied to a microwave reaction apparatus, and reacted at 80° C. for 1 hour.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure, and 10 ml of ethyl acetate and 10 ml of 10% potassium dihydrogen phosphate were added to the obtained concentration residue, and then the aqueous layer and the organic layer were separated. The aqueous layer was subjected to extraction with 10 ml of dichloromethane twice, and all of the obtained organic layers were washed with 10 ml of water, 10 ml of a saturated aqueous solution of sodium bicarbonate, and 10 ml of a saturated aqueous solution of sodium chloride in this order, then dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: 1,2-dichloroethane:ethyl acetate=100:0 to 51:49 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. Purified water was added to the obtained concentration residue, and after ultrasonication, insoluble matter was filtered and dried under reduced pressure to obtain 39 mg of the title compound (yield: 19%) as a white solid.

Mass spectrum (CI, m/z): 554 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.20 & 11.63 (br s, total 1H), 9.54 (s, 1H), 7.44-7.37 (m, 2H), 7.36-7.30 (m, 2H), 7.28-7.21 (m, 1H), 6.66-6.39 (m, 1H), 5.14-5.04 (m, 1H), 4.59-4.40 (m, 2H), 4.25 (d, J=7.5 Hz, 2H), 2.49-2.41 (m, 2H), 2.29-2.14 (m, 4H), 1.92-1.73 (m, 2H), 1.61 (br s, 3H), 1.56-1.41 (m, 5H), 1.29-1.18 (m, 2H), 0.80 (t, J=7.3 Hz, 3H), 0.09 (s, 9H).

(S)-2-{6,6-Dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazole-5-carboxamido}-2-phenylethyl octanoate (Compound No. V-1470)

To a solution of 183 mg (0.329 mmol) of a mixture of (S)-ethyl 5-[(2-hydroxy-1-phenylethyl)carbamoyl]-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-1(4H)-carboxylate synthesized in the similar manner as in Reference Example 38 and (S)-ethyl 5-[(2-hydroxy-1-phenylethyl)carbamoyl]-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate in a 3 ml of dehydrated dichloromethane, 0.10 ml (0.72 mmol) of triethylamine, 0.15 ml (0.51 mmol) of n-octanoic anhydride, and 10.6 mg (0.087 mmol) of 4-dimethylaminopyridine were added in this order at room temperature in a nitrogen atmosphere and then stirred at the same temperature as above for 2 hours. Subsequently, 1.0 ml (7.2 mmol) of triethylamine and 1.0 ml (25 mmol) of methanol were added to the reaction solution and then stirred at room temperature for 20.5 hours. 1.0 ml (7.2 mmol) of triethylamine and 1.0 ml (25 mmol) of methanol were added to the reaction solution, stirred at 50° C. for 2 hours, and then stirred for 4 hours after the temperature was raised to 60° C.

After the completion of the reaction, water was added to the reaction solution, followed by extraction with dichloromethane three times. All of the obtained organic layers were dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (elution solvent: dichloromethane:methanol=100:0 to 97:3 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. n-Hexane was added to the obtained concentration residue, and after ultrasonication, the deposited solid was collected by filtration, washed by sousing with n-hexane, and then dried under reduced pressure to obtain 115 mg of the title compound (yield: 58%) as a white solid.

Mass spectrum (CI, m/z): 596 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.16 & 11.77 (br s, total 1H), 9.55 (br s, 1H), 7.47-7.37 (m, 2H), 7.37-7.29 (m, 2H), 7.29-7.20 (m, 1H), 6.64-6.43 (m, 1H), 5.16-5.02 (m, 1H), 4.49 (s, 2H), 4.34-4.18 (m, 2H), 2.49-2.41 (m, 2H), 2.28-2.14 (m, 4H), 1.89-1.73 (m, 2H), 1.60 (s, 3H), 1.53 (s, 3H), 1.50-1.43 (m, 2H), 1.24-1.13 (m, 8H), 0.83-0.75 (m, 3H), 0.09 (s, 9H).

(S)-2-{6,6-Dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazole-5-carboxamido}-2-phenylethyl dodecanoate (Compound No. V-1474)

To a solution of 202 mg (0.373 mmol) of (S)-ethyl 5-[(2-hydroxy-1-phenylethyl)carbamoyl]-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 38, 0.11 ml (0.79 mmol) of triethylamine, and 10 mg (0.082 mmol) of 4-dimethylaminopyridine in 2 ml of dehydrated dichloromethane, 224 mg (0.585 mmol) of dodecanoic anhydride was added at room temperature in an argon atmosphere and stirred at room temperature for 1 hour. Subsequently, 1 ml of triethylamine and 1 ml of methanol were added to the reaction solution and stirred at room temperature for 16 hours.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel chromatography (elution solvent: n-hexane:ethyl acetate=95:5 to 50:50 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure and dried under reduced pressure to obtain 139 mg of the title compound (yield: 57%) as a white solid.

Mass spectrum (CI, m/z): 652 [M+1] +

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.18 & 11.66 (br s, total 1H), 9.83-9.28 (m, 1H), 7.42-7.37 (m, 2H), 7.37-7.30 (m, 2H), 7.28-7.21 (m, 1H), 6.67-6.35 (m, 1H), 5.14-5.03 (m, 1H), 4.56-4.42 (m, 2H), 4.30-4.20 (m, 2H), 2.49-2.42 (m, 2H), 2.28-2.13 (m, 4H), 1.89-1.73 (m, 2H), 1.60 (br s, 3H), 1.57-1.43 (m, 5H), 1.30-1.14 (m, 16H), 0.85 (t, J=6.9 Hz, 3H), 0.09 (s, 9H).

(S)-2-{6,6-Dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazole-5-carboxamido}-2-phenylethyl palmitate (Compound No. V-1478)

To a solution of 220 mg (0.406 mmol) of (S)-ethyl 5-[(2-hydroxy-1-phenylethyl)carbamoyl]-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 38, 0.115 ml (0.825 mmol) of triethylamine, and 300 mg (0.606 mmol) of palmitic anhydride in 3 ml of dichloromethane, 10 mg (0.082 mmol) of 4-dimethylaminopyridine was added at room temperature in an argon atmosphere and stirred at the same temperature as above for 1.5 hours. Subsequently, 1.0 ml of methanol and 0.5 ml of triethylamine were added to the reaction solution and stirred at room temperature for 15 hours.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel chromatography (elution solvent: n-hexane:ethyl acetate=90:10 to 50:50 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure and dried under reduced pressure to obtain 195 mg of the title compound (yield: 68%) as a white solid.

Mass spectrum (DUIS, m/z): 708 [M+1] +

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.18 & 11.64 (br s, total 1H), 9.64-9.50 (m, 1H), 7.43-7.38 (m, 2H), 7.36-7.30 (m, 2H), 7.27-7.21 (m, 1H), 6.63-6.39 (m, 1H), 5.13-5.04 (m, 1H), 4.55-4.42 (m, 2H), 4.30-4.20 (m, 2H), 2.48-2.40 (m, 2H), 2.29-2.14 (m, 4H), 1.89-1.74 (m, 2H), 1.60 (br s, 3H), 1.57-1.43 (m, 5H), 1.29-1.14 (m, 24H), 0.89-0.81 (m, 3H), 0.09 (s, 9H).

(S)-2-{6,6-Dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazole-5-carboxamido}-2-phenylethyl isobutanoate (Compound No. V-1454)

To a solution of 247 mg (0.456 mmol) of (S)-ethyl 5-[(2-hydroxy-1-phenylethyl)carbamoyl]-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 38 in 3 ml of dehydrated dichloromethane, 0.15 ml (1.1 mmol) of triethylamine and 0.060 ml (0.57 mmol) of isobutyryl chloride were added in this order at room temperature in a nitrogen atmosphere and then stirred at the same temperature as above for 100 minutes. Subsequently, 1.0 ml (7.2 mmol) of triethylamine and 1.0 ml (25 mmol) of methanol were added to the reaction solution and then stirred at room temperature for 4.5 hours.

After the completion of the reaction, water was added to the reaction solution, followed by extraction with dichloromethane three times. All of the obtained organic layers were dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: dichloromethane:methanol=100:0 to 99:1 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. For the obtained concentration residue, crystallization was performed with ethyl acetate/n-hexane, and the obtained solid was collected by filtration, washed by sousing with n-hexane, and then dried under reduced pressure to obtain 202 mg of the title compound (yield: 82%) as a white solid.

Mass spectrum (CI, m/z): 540 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.20 & 11.61 (br s, total 1H), 9.53 (s, 1H), 7.47-7.38 (m, 2H), 7.38-7.29 (m, 2H), 7.29-7.20 (m, 1H), 6.71-6.34 (m, 1H), 5.20-5.03 (m, 1H), 4.57-4.38 (m, 2H), 4.33-4.15 (m, 2H), 2.48-2.42 (m, 3H), 2.27-2.13 (m, 2H), 1.92-1.73 (m, 2H), 1.65-1.47 (m, 6H), 1.08-0.99 (m, 6H), 0.14-0.05 (m, 9H).

(S)-2-{6,6-Dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazole-5-carboxamido}-2-phenylethyl pivalate (Compound No. V-1462)

To a solution of 210 mg (0.387 mmol) of (S)-ethyl 5-[(2-hydroxy-1-phenylethyl)carbamoyl]-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 38 and 0.11 ml (0.79 mmol) of triethylamine in 3 ml of dehydrated dichloromethane, 0.12 ml (0.59 mmol) of pivalic anhydride and 10.5 mg (0.086 mmol) of 4-dimethylaminopyridine were added in an argon atmosphere and stirred at room temperature for 4.5 hours. Subsequently, 0.5 ml of triethylamine and 1 ml of methanol were added to the reaction solution and reacted at room temperature for 14 hours.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel chromatography (elution solvent: n-hexane:ethyl acetate=90:10 to 50:50 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure and dried under reduced pressure. Diisopropyl ether was added to the obtained concentration residue, and after ultrasonication, insoluble matter was collected by filtration and dried under reduced pressure to obtain 144 mg of the title compound (yield: 67%) as a white solid.

Mass spectrum (CI, m/z): 554 [M+1] +

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.20 & 11.66 (br s, total 1H), 9.55 (s, 1H), 7.45-7.38 (m, 2H), 7.37-7.31 (m, 2H), 7.28-7.22 (m, 1H), 6.68-6.40 (m, 1H), 5.20-5.09 (m, 1H), 4.48 (br s, 2H), 4.29-4.19 (m, 2H), 2.49-2.41 (m, 2H), 2.26-2.14 (m, 2H), 1.90-1.74 (m, 2H), 1.59 (s, 3H), 1.55 (s, 3H), 1.08 (s, 9H), 0.09 (s, 9H).

(S)-2-{6,6-Dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazole-5-carboxamido}-2-phenylethyl 3-methylbutanoate (Compound No. V-1466)

To a solution of 201 mg (0.371 mmol) of a mixture of (S)-ethyl 5-[(2-hydroxy-1-phenylethyl)carbamoyl]-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-1(4H)-carboxylate synthesized in the similar manner as in Reference Example 38 and (S)-ethyl 5-[(2-hydroxy-1-phenylethyl)carbamoyl]-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate and 0.10 ml (0.74 mmol) of triethylamine in 3 ml of dichloromethane, 0.11 ml (0.56 mmol) of isovaleric anhydride and 10.6 mg (0.087 mmol) of 4-dimethylaminopyridine were added at room temperature in an argon atmosphere and then reacted at the same temperature as above for 3 hours. Subsequently, 1.0 ml of methanol and 0.5 ml of triethylamine were added and reacted at room temperature for 15.5 hours, then the reaction solution was concentrated under reduced pressure, and 1.0 ml of methanol and 0.5 ml of triethylamine were added again to the obtained concentration residue and reacted at 40° C. for 6 hours.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure, and 8 ml of ethyl acetate, 0.4 ml of water, and 8 ml of a saturated aqueous solution of sodium chloride were added to the obtained concentration residue, and then the aqueous layer and the organic layer were separated. The aqueous layer was subjected to extraction with 10 ml of dichloromethane twice, and all of the obtained organic layers were dried over anhydrous magnesium sulfate, then filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: 1,2-dichloroethane:methanol=100:0 to 95:5 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. Diethyl ether was added to the obtained concentration residue, ultrasonicated, and then concentrated under reduced pressure. Water was added to the obtained concentration residue, ultrasonicated, and left standing overnight, and then, insoluble matter was filtered and dried under reduced pressure to obtain 97 mg of the title compound (yield: 47%) as a white solid.

Mass spectrum (CI, m/z): 554 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.50-11.49 (m, 1H), 9.55 (s, 1H), 7.44-7.38 (m, 2H), 7.37-7.30 (m, 2H), 7.29-7.22 (m, 1H), 6.84-6.25 (m, 1H), 5.13-5.06 (m, 1H), 4.55-4.41 (m, 2H), 4.31-4.21 (m, 2H), 2.49-2.42 (m, 2H), 2.26-2.11 (m, 4H), 2.01-1.87 (m, 1H), 1.87-1.74 (m, 2H), 1.59 (s, 3H), 1.53 (s, 3H), 0.87-0.82 (m, 6H), 0.09 (s, 9H).

(S)-2-{6,6-Dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazole-5-carboxamido}-2-phenylethyl benzoate (Compound No. V-1482)

To a solution of 132 mg (0.244 mmol) of (S)-ethyl 5-[(2-hydroxy-1-phenylethyl)carbamoyl]-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 38 and 0.068 ml (0.49 mmol) of triethylamine in 2.5 ml of dehydrated dichloromethane, 0.042 ml (0.36 mmol) of benzoyl chloride was added at room temperature in an argon atmosphere and stirred at the same temperature as above for 1 hour. Subsequently, 0.5 ml of triethylamine and 0.5 ml of methanol were added to the reaction solution and stirred at room temperature for 20 hours.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel chromatography (elution solvent: n-hexane:ethyl acetate=90:10 to 50:50 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure and dried under reduced pressure to obtain 94 mg of the title compound (yield: 67%) as a white solid.

Mass spectrum (CI, m/z): 574 [M+1] +

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.19 & 11.71 (br s, total 1H), 9.55 (br s, 1H), 7.95-7.91 (m, 2H), 7.66-7.60 (m, 1H), 7.52-7.46 (m, 4H), 7.39-7.33 (m, 2H), 7.30-7.24 (m, 1H), 6.73-6.59 (m, 1H), 5.35-5.26 (m, 1H), 4.57-4.44 (m, 4H), 2.48-2.42 (m, 2H), 2.23-2.15 (m, 2H), 1.87-1.73 (m, 2H), 1.57 (s, 3H), 1.55 (s, 3H), 0.08 (s, 9H).

(S)-2-{6,6-Dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazole-5-carboxamido}-2-phenylethyl ethyl carbonate (Compound No. V-1486)

To a solution of 265 mg (0.490 mmol) of (S)-ethyl 5-[(2-hydroxy-1-phenylethyl)carbamoyl]-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 38 in 4 ml of dehydrated dichloromethane, 0.14 ml (1.0 mmol) of triethylamine and 0.060 ml (0.63 mmol) of ethyl chloroformate were added in this order at room temperature in a nitrogen atmosphere and then stirred at the same temperature as above for 2 hours. Then, 0.20 ml (1.4 mmol) of triethylamine and 0.10 ml (1.1 mmol) of ethyl chloroformate were added at room temperature and stirred at the same temperature as above for 1.5 hours. 0.20 ml (1.4 mmol) of triethylamine and 0.10 ml (1.1 mmol) of ethyl chloroformate were further added again at room temperature and stirred at the same temperature as above for 1 hour. Subsequently, 1.0 ml (7.2 mmol) of triethylamine and 1.0 ml (25 mmol) of methanol were added to the reaction solution and then stirred at room temperature for 4 hours.

After the completion of the reaction, water was added to the reaction solution, followed by extraction with dichloromethane three times. All of the obtained organic layers were dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: dichloromethane:methanol=100:0 to 98:2 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was subjected to preparative HPLC (column: X-Bridge (trade name) ODS, elution solvent: acetonitrile:1 mM aqueous dipotassium hydrogen phosphate solution=45:55 (V/V)), a fraction containing the compound of interest was concentrated under reduced pressure, and acetonitrile was distilled off. The deposited solid was collected by filtration, washed by sousing with pure water, and then dried under reduced pressure to obtain 60 mg of the title compound (yield: 23%) as a white solid.

Mass spectrum (ESI, m/z): 542 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.20 & 11.65 (br s, total 1H), 9.62-9.49 (m, 1H), 7.44-7.31 (m, 4H), 7.28-7.21 (m, 1H), 6.68-6.45 (m, 1H), 5.21-4.99 (m, 1H), 4.59-4.40 (m, 2H), 4.38-4.22 (m, 2H), 4.10 (q, J=7.0 Hz, 2H), 2.56-2.42 (m, 2H), 2.27-2.14 (m, 2H), 1.93-1.73 (m, 2H), 1.69-1.45 (m, 6H), 1.18 (t, J=7.0 Hz, 3H), 0.17-0.04 (m, 9H).

Sodium (S)-4-(2-{6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazole-5-carboxamido}-2-phenylethoxy)-4-oxobutanoate (sodium salt of Compound No. V-1490)

To a solution of 201 mg (0.456 mmol) of ethyl 5-(chlorocarbonyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 3 in 7.0 ml of 1,4-dioxane, 628 mg of (S)-2-amino-2-phenylethyl benzyl succinate trifluoroacetate (containing impurities) synthesized in the similar manner as in Reference Example 40 and 1.0 ml (5.7 mmol) of DIPEA were added, applied to a microwave reaction apparatus, and reacted at 100° C. for 1 hour. Subsequently, 1 ml of methanol and 1 ml of triethylamine were added, applied to a microwave reaction apparatus, and reacted at 80° C. for 3 hours.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure, ethyl acetate was added to the obtained concentration residue, washed with a 10% aqueous potassium dihydrogen phosphate solution, water, a saturated aqueous solution of sodium bicarbonate, and a saturated aqueous solution of sodium chloride in this order, then dried over anhydrous magnesium sulfate, and filtered, and then, the filtrate was concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: 1,2-dichloroethane:ethyl acetate=100:0 to 70:30 (V/V)), and a fraction containing (S)-benzyl (2-{6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazole-5-carboxamido}-2-phenylethyl)succinate was concentrated under reduced pressure to obtain a concentration residue.

To a solution of 171 mg of the obtained concentration residue in 20 ml of ethanol, 25.4 mg of palladium/carbon (ASCA2 (trade name), manufactured by N.E. Chemcat Corp., containing 52% water) was added in a nitrogen atmosphere and then, after replacement with a hydrogen atmosphere under reduced pressure, stirred at room temperature for 2 hours.

After the completion of the reaction, replacement with an argon atmosphere was performed, and the reaction solution was filtered through celite. 0.26 ml (0.26 mmol) of a 1 N aqueous sodium hydroxide solution was added to the filtrate and concentrated under reduced pressure. Diethyl ether was added to the obtained residue and then ultrasonicated, and the deposited solid was collected by filtration and dried under reduced pressure to obtain 147 mg of the title compound (yield: 54% [2 steps]) as a white solid.

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 13.32 (br s, 1H), 10.75 (br s, 1H), 7.44-7.38 (m, 2H), 7.36-7.29 (m, 2H), 7.28-7.19 (m, 1H), 6.47 (d, J=7.3 Hz, 1H), 5.11-5.02 (m, 1H), 4.57-4.41 (m, 2H), 4.28 (dd, J=5.6, 10.8 Hz, 1H), 4.17 (dd, J=8.0, 10.8 Hz, 1H), 2.49-2.42 (m, 2H), 2.35 (t, J=7.2 Hz, 2H), 2.25-2.16 (m, 2H), 2.11 (t, J=7.2 Hz, 2H), 1.87-1.71 (m, 2H), 1.58 (s, 3H), 1.51 (s, 3H), 0.08 (s, 9H).

(S)-(2-{6,6-Dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazole-5-carboxamido}-2-phenylethoxy)methyl pivalate (Compound No. VI-474)

To a solution of 272 mg (1.08 mmol) of (S)-(2-amino-2-phenylethoxy)methyl pivalate synthesized in the similar manner as in Reference Example 42 in 2 ml of dehydrated THF, 0.15 ml (0.86 mmol) of DIPEA and 162 mg (0.368 mmol) of ethyl 5-(chlorocarbonyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 3 were added in this order at room temperature in a nitrogen atmosphere and then stirred for 130 minutes while heated to reflux. Subsequently, 1.0 ml of triethylamine and 0.8 ml of methanol were added to the reaction solution and then stirred for 70 minutes while heated to reflux.

After the completion of the reaction, water was added to the reaction solution, followed by extraction with dichloromethane three times. All of the obtained organic layers were dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DNH silica gel, elution solvent: dichloromethane:methanol=100:0 to 98:2 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. For the obtained concentration residue, crystallization was performed with ethyl acetate/n-hexane, and the deposited solid was collected by filtration, washed by sousing with n-hexane, and then dried under reduced pressure to obtain 176 mg of the title compound (yield: 82%) as a white solid.

Mass spectrum (CI, m/z): 584 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.20 & 11.64 (br s, total 1H), 9.59-9.49 (m, 1H), 7.41-7.35 (m, 2H), 7.35-7.27 (m, 2H), 7.25-7.19 (m, 1H), 6.42 & 6.28 (d, J=8.0 Hz, total 1H), 5.29 (d, J=6.2 Hz, 1H), 5.22 (d, J=6.2 Hz, 1H), 5.02-4.94 (m, 1H), 4.57-4.37 (m, 2H), 3.91-3.83 (m, 1H), 3.79 (dd, J=6.0, 10.0 Hz, 1H), 2.49-2.40 (m, 2H), 2.28-2.13 (m, 2H), 1.92-1.73 (m, 2H), 1.67-1.45 (m, 6H), 1.13 (s, 9H), 0.14-0.06 (m, 9H).

(S)-2-Acetoxy-1-phenylethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxylate (Compound No. V-1250)

To a solution of 412 mg of ethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate (containing impurities) synthesized in the similar manner as in Reference Example 3 by using 506 mg (1.06 mmol) of 5-tert-butyl 2-ethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]pyrrolo[3,4-c]pyrazole-2,5(4H,6H)-dicarboxylate synthesized in the similar manner as in Reference Example 84 in 4 ml of dehydrated THF, 0.70 ml (4.0 mmol) of DIPEA and 1.30 g (3.84 mmol) of (S)-2-({[(2,5-dioxopyrrolidin-1-yl)oxy]carbonyl}oxy)-2-phenylethyl acetate synthesized in the similar manner as in Reference Example 43 were added in this order at room temperature in a nitrogen atmosphere and then stirred for 1.5 hours while heated to reflux. Subsequently, 2.0 ml (14 mmol) of triethylamine and 1.5 ml (37 mmol) of methanol were added to the reaction solution and then stirred for 3.5 hours while heated to reflux.

After the completion of the reaction, water was added to the reaction solution, followed by extraction with dichloromethane three times. All of the obtained organic layers were dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=80:20 to 50:50 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure to obtain 225 mg of a concentration residue.

Approximately 50 mg of the obtained concentration residue was subjected to preparative HPLC (column: X-Bridge (trade name) ODS, elution solvent: acetonitrile:1 mM aqueous dipotassium hydrogen phosphate solution=50:50 (V/V)), a fraction containing the compound of interest was concentrated under reduced pressure, and acetonitrile was distilled off. The concentration residue was subjected to extraction with ethyl acetate twice, and all of the obtained organic layers were dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. For the obtained concentration residue, crystallization was performed with ethyl acetate/diisopropyl ether/n-hexane, and the deposited solid was collected by filtration, washed by sousing with n-hexane, and then dried under reduced pressure to obtain 11.6 mg of the title compound (yield: 2% [2 steps]) as a white solid.

Mass spectrum (CI, m/z): 513 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.35-12.21 & 11.97-11.83 (m, total 1H), 9.87-9.45 (m, 1H), 7.47-7.24 (m, 5H), 5.99-5.85 (m, 1H), 4.65-4.17 (m, 4H), 2.48-2.36 (m, 2H), 2.28-2.10 (m, 2H), 2.05-1.95 (m, 3H), 1.92-1.72 (m, 2H), 1.71-1.43 (m, 6H), 0.16-0.02 (m, 9H).

(S)-Benzyl 2-{6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazole-5-carboxamido}-2-phenylacetate (Compound No. IV-411)

To a solution of 195 mg (0.442 mmol) of ethyl 5-(chlorocarbonyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 3 in 7 ml of 1,4-dioxane, 565 mg of (S)-benzyl 2-amino-2-phenylacetate trifluoroacetate (containing impurities) synthesized in the similar manner as in Reference Example 45 and 0.50 ml (2.9 mmol) of DIPEA were added at room temperature in an argon atmosphere, then applied to a microwave reaction apparatus, and stirred at 100° C. for 1 hour. After the reaction, the reaction solution was concentrated under reduced pressure, and 4 ml of methanol and 1 ml of triethylamine were added to the obtained concentration residue, applied to a microwave reaction apparatus, and reacted at 80° C. for 1 hour.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure, ethyl acetate was added to the obtained concentration residue, the organic layer after washing with a 10% aqueous potassium dihydrogen phosphate solution, a saturated aqueous solution of sodium bicarbonate, and a saturated aqueous solution of sodium chloride in this order was dried over anhydrous magnesium sulfate and filtered, and then, the filtrate was concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: 1,2-dichloroethane:ethyl acetate=100:0 to 55:45 (V/V)), and a fraction composed mainly of the title compound and a fraction composed mainly of a by-product [(S)-methyl 2-{6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazole-5-carboxamido}-2-phenylacetate] were each concentrated under reduced pressure. The concentration residue of the fraction composed mainly of the title compound was subjected again to silica gel column chromatography (DIOL silica gel, elution solvent: 1,2-dichloroethane:ethyl acetate=100:0 to 55:45 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure to obtain 99 mg of the title compound (yield: 39%) as a white foam.

Mass spectrum (DUIS, m/z): 574 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.21 & 11.70 (br s, total 1H), 9.63-9.44 (m, 1H), 7.51-7.41 (m, 2H), 7.38-7.23 (m, 8H), 6.81-6.47 (m, 1H), 5.42 (d, J=7.2 Hz, 1H), 5.17 (d, J=12.7 Hz, 1H), 5.11 (d, J=12.7 Hz, 1H), 4.61-4.39 (m, 2H), 2.49-2.38 (m, 2H), 2.25-2.12 (m, 2H), 1.91-1.72 (m, 2H), 1.68-1.52 (m, 6H), 0.07 (s, 9H).

(S)-Methyl 2-{6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazole-5-carboxamido}-2-phenylacetate (Compound No. IV-419)

The concentration residue of the fraction composed mainly of the title compound collected at the time of the first purification of silica gel column chromatography in the operational steps of Example 55 was subjected again to silica gel column chromatography (DIOL silica gel, elution solvent: 1,2-dichloroethane:ethyl acetate=100:0 to 55:45 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure to obtain 29 mg of the title compound (yield: 13%) as a white foam.

Mass spectrum (DUIS, m/z): 498 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.21 & 11.71 (br s, total 1H), 9.63-9.46 (m, 1H), 7.48-7.41 (m, 2H), 7.40-7.28 (m, 3H), 6.73-6.56 (m, 1H), 5.36 (d, J=7.2 Hz, 1H), 4.61-4.38 (m, 2H), 3.62 (s, 3H), 2.49-2.38 (m, 2H), 2.27-2.10 (m, 2H), 1.92-1.71 (m, 2H), 1.67-1.51 (m, 6H), 0.08 (s, 9H).

N-(2,2-Difluoro-3-hydroxy-1-phenylpropyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. IV-362)

To a solution of 249 mg (1.33 mmol) of 3-amino-2,2-difluoro-3-phenylpropan-1-ol synthesized in the similar manner as in Reference Example 48 in 2 ml of dehydrated 1,4-dioxane, 0.30 ml (1.7 mmol) of DIPEA and 178 mg (0.403 mmol) of ethyl 5-(chlorocarbonyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 3 were added in this order at room temperature in a nitrogen atmosphere and then stirred at 80° C. for 7 hours. Subsequently, 0.10 ml (1.7 mmol) of 2-aminoethanol was added to the reaction solution allowed to cool to room temperature, and then stirred at room temperature for 1.5 hours.

After the completion of the reaction, a saturated aqueous solution of sodium bicarbonate was added to the reaction solution and stirred, followed by extraction with dichloromethane three times. All of the organic layers were dried over anhydrous magnesium sulfate, then filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=60:40 to 30:70 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was dissolved in ethyl acetate, then n-hexane was added, and the deposited solid was collected by filtration, washed with n-hexane, and then dried under reduced pressure to obtain 155 mg of the title compound (yield: 74%) as a white solid.

Mass spectrum (CI, m/z): 520 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.43-11.84 (m, 1H), 10.02-9.36 (m, 1H), 7.56-7.50 (m, 2H), 7.40-7.27 (m, 3H), 6.61 (br s, 1H), 5.71 (br s, 1H), 5.49-5.34 (m, 1H), 4.70-4.56 (m, 1H), 4.47 (br d, J=12.0 Hz, 1H), 3.73-3.45 (m, 2H), 2.57-2.42 (m, 2H), 2.26-2.15 (m, 2H), 1.90-1.74 (m, 2H), 1.61 (s, 3H), 1.51 (s, 3H), 0.09 (s, 9H).

N-(2-Isopropoxy-1-phenylethyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. IV-146)

To a solution of 0.102 g (0.231 mmol) of ethyl 5-(chlorocarbonyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 3 and 0.127 g (0.709 mmol) of 2-isopropoxy-1-phenylethanamine synthesized in the similar manner as in Reference Example 50 in 2.5 ml of dehydrated 1,4-dioxane, 0.200 ml (1.15 mmol) of DIPEA was added at room temperature in a nitrogen atmosphere and then heated and stirred at 100° C. for 1 hour. After standing to cool, 0.50 ml (12 mmol) of methanol and 0.070 ml (1.2 mmol) of 2-aminoethanol were added to the reaction solution and stirred at room temperature for 1 hour.

After the completion of the reaction, ethyl acetate was added to the residue obtained by concentration under reduced pressure, the organic layer after washing with a 10% aqueous potassium dihydrogen phosphate solution, a saturated aqueous solution of sodium bicarbonate, and a saturated aqueous solution of sodium chloride in this order was dried over anhydrous magnesium sulfate and filtered, and then, the filtrate was concentrated under reduced pressure. The residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: 1,2-dichloroethane:ethyl acetate=100:0 to 50:50 (V/V)), a fraction containing the compound of interest was concentrated under reduced pressure, the residue was dissolved in a small amount of dichloromethane, and after addition of n-hexane and ultrasonication, the deposited solid was collected by filtration and dried under reduced pressure to obtain 0.106 g of the title compound (yield: 90%) as a white solid.

Mass spectrum (CI, m/z): 512 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.21 & 11.76 (br s, total 1H), 9.68-9.50 (m, 1H), 7.42-7.16 (m, 5H), 6.31-6.08 (m, 1H), 4.94-4.84 (m, 1H), 4.56-4.37 (m, 2H), 3.67-3.51 (m, 3H), 2.51-2.40 (m, 2H), 2.27-2.13 (m, 2H), 1.92-1.71 (m, 2H), 1.65-1.48 (m, 6H), 1.08-1.03 (m, 6H), 0.09 (s, 9H).

6,6-Dimethyl-N-(2-phenoxy-1-phenylethyl)-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. IV-162)

To a solution of 0.101 g (0.230 mmol) of ethyl 5-(chlorocarbonyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 3 and 0.145 g (0.681 mmol) of 2-phenoxy-1-phenylethanamine synthesized in the similar manner as in Reference Example 52 in 2.5 ml of dehydrated 1,4-dioxane, 0.200 ml (1.15 mmol) of DIPEA was added at room temperature in a nitrogen atmosphere and then stirred at 100° C. for 1 hour. After standing to cool, 0.50 ml (12 mmol) of methanol and 0.070 ml (1.2 mmol) of 2-aminoethanol were added and stirred at room temperature for 1 hour.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure, ethyl acetate was added, the organic layer after washing with a 10% aqueous potassium dihydrogen phosphate solution, a saturated aqueous solution of sodium bicarbonate, and a saturated aqueous solution of sodium chloride in this order was dried over anhydrous magnesium sulfate and filtered, and then, the filtrate was concentrated under reduced pressure. The residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: 1,2-dichloroethane:ethyl acetate=100:0 to 67:33 (V/V)), a fraction containing the compound of interest was concentrated under reduced pressure, the residue was dissolved in a small amount of dichloromethane, and after addition of n-hexane and ultrasonication, the deposited solid was collected by filtration and dried under reduced pressure to obtain 0.112 g of the title compound (yield: 89%) as a white solid.

Mass spectrum (CI, m/z): 546 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.21 & 11.70 (br s, total 1H), 9.57 (br s, 1H), 7.51-7.18 (m, 7H), 7.03-6.86 (m, 3H), 6.68-6.40 (m, 1H), 5.23-5.11 (m, 1H), 4.57-4.38 (m, 2H), 4.34-4.22 (m, 1H), 4.16 (dd, J=5.9, 9.8 Hz, 1H), 2.57-2.39 (m, 2H), 2.25-2.11 (m, 2H), 1.90-1.71 (m, 2H), 1.62 (br s, 3H), 1.54 (br s, 3H), 0.08 (s, 9H).

(S)—N-[1-(2-Chlorophenyl)-2-hydroxyethyl]-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. IV-959)

To a solution of 0.105 g (0.238 mmol) of ethyl 5-(chlorocarbonyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 3 and 0.124 g (0.723 mmol) of (S)-2-amino-2-(2-chlorophenyl)ethanol [purchased from Amatek Chemical Co., Ltd.] in 2.5 ml of dehydrated 1,4-dioxane, 0.200 ml (1.15 mmol) of DIPEA was added at room temperature in a nitrogen atmosphere and then stirred at 100° C. for 1 hour. After standing to cool, 0.50 ml (12 mmol) of methanol and 0.070 ml (1.2 mmol) of 2-aminoethanol were added and stirred at room temperature for 1 hour.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure, ethyl acetate was added to the residue, the organic layer after washing with a 10% aqueous potassium dihydrogen phosphate solution, a saturated aqueous solution of sodium bicarbonate, and a saturated aqueous solution of sodium chloride in this order was dried over anhydrous magnesium sulfate and filtered, and then, the filtrate was concentrated under reduced pressure. The residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: 1,2-dichloroethane:ethyl acetate=84:16 to 33:67 (V/V)), a fraction containing the compound of interest was concentrated under reduced pressure, the residue was dissolved in a small amount of dichloromethane, and after addition of n-hexane and ultrasonication, the deposited solid was collected by filtration and dried under reduced pressure to obtain 0.0958 g of the title compound (yield: 80%) as a white solid.

Mass spectrum (DUIS, m/z): 504 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.21 & 11.75 (br s, total 1H), 9.71-9.52 (m, 1H), 7.51 (dd, J=1.6, 7.7 Hz, 1H), 7.38 (dd, J=1.2, 7.8 Hz, 1H), 7.33-7.20 (m, 2H), 6.36-6.14 (m, 1H), 5.21-5.12 (m, 1H), 5.04 (t, J=6.0 Hz, 1H), 4.66-4.45 (m, 2H), 3.64-3.48 (m, 2H), 2.57-2.41 (m, 2H), 2.28-2.13 (m, 2H), 1.91-1.72 (m, 2H), 1.66-1.42 (m, 6H), 0.10 (s, 9H).

(S)—N-[2-Hydroxy-1-(o-tolyl)ethyl]-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. IV-1067)

To a solution of 0.104 g (0.235 mmol) of ethyl 5-(chlorocarbonyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 3 and 0.131 g (0.696 mmol) of (S)-2-amino-2-(o-tolyl)ethanol hydrochloride [purchased from Acesys Pharmatech Ltd.] in 2.5 ml of dehydrated 1,4-dioxane, 0.400 ml (2.30 mmol) of DIPEA was added at room temperature in a nitrogen atmosphere and then heated and stirred at 100° C. for 1 hour. After standing to cool, 0.50 ml (12 mmol) of methanol and 0.070 ml (1.2 mmol) of 2-aminoethanol were added and stirred at room temperature for 1 hour.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure, ethyl acetate was added, the organic layer after washing with a 10% aqueous potassium dihydrogen phosphate solution, a saturated aqueous solution of sodium bicarbonate, and a saturated aqueous solution of sodium chloride in this order was dried over anhydrous magnesium sulfate and filtered, and then, the filtrate was concentrated under reduced pressure. The residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: 1,2-dichloroethane:ethyl acetate=84:16 to 33:67 (V/V)), a fraction containing the compound of interest was concentrated under reduced pressure, the residue was dissolved in a small amount of dichloromethane, and after addition of n-hexane and ultrasonication, the deposited solid was collected by filtration and dried under reduced pressure to obtain 0.0738 g of the title compound (yield: 65%) as a white solid.

Mass spectrum (CI, m/z): 484 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.20 & 11.66 (br s, total 1H), 9.63-9.50 (m, 1H), 7.40 (d, J=7.4 Hz, 1H), 7.18-7.03 (m, 3H), 6.28-6.05 (m, 1H), 5.04-4.95 (m, 1H), 4.89 (t, J=6.0 Hz, 1H), 4.58-4.41 (m, 2H), 3.61-3.43 (m, 2H), 2.56-2.41 (m, 2H), 2.36 (s, 3H), 2.27-2.11 (m, 2H), 1.93-1.70 (m, 2H), 1.69-1.41 (m, 6H), 0.10 (s, 9H).

(S)—N-(1-Hydroxy-3-phenylpropan-2-yl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. IV-862)

To a solution of 101 mg (0.229 mmol) of ethyl 5-(chlorocarbonyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 3 in 3 ml of 1,4-dioxane, 0.115 ml (0.673 mmol) of DIPEA and 102 mg (0.675 mmol) of (S)-2-amino-3-phenylpropan-1-ol were added in this order in an argon atmosphere and then stirred at 100° C. for 1 hour. Subsequently, the reaction solution was concentrated under reduced pressure, and 2 ml of methanol and 0.5 ml of triethylamine were added in this order at room temperature and stirred at 80° C. for 1 hour in a microwave reaction apparatus.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure, the concentration residue was dissolved in 5 ml of ethyl acetate and washed with a 5% aqueous potassium dihydrogen phosphate solution twice, and then, the organic layer was washed with 5 ml of a saturated aqueous solution of sodium bicarbonate. The organic layer was dried over anhydrous magnesium sulfate, then filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: ethyl acetate:methanol=100:0 to 86:14 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure and subsequently dried under reduced pressure at 50° C. to obtain 88.5 mg of the title compound (yield: 80%) as a white solid.

Mass spectrum (CI, m/z): 484 [M+1]+.

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.19 & 11.71 (br s, total 1H), 9.54 (br s, 1H), 7.28-7.18 (m, 4H), 7.18-7.12 (m, 1H), 5.72-5.45 (m, 1H), 4.77 (t, J=5.5 Hz, 1H), 4.46-4.17 (m, 2H), 3.90-3.77 (m, 1H), 3.44-3.28 (m, 2H), 2.87-2.70 (m, 2H), 2.54-2.40 (m, 2H), 2.25-2.13 (m, 2H), 1.92-1.70 (m, 2H), 1.58 (br s, 3H), 1.50 (br s, 3H), 0.09 (s, 9H).

N-(2-Hydroxy-3-methylbutyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. IV-446)

To a solution of 103 mg (0.234 mmol) of ethyl 5-(chlorocarbonyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 3 in 3 ml of 1,4-dioxane, 69.8 mg (0.677 mmol) of 1-amino-3-methylbutan-2-ol [purchased from Life Chemicals Inc.] and 0.115 ml (0.673 mmol) of DIPEA were added in this order at room temperature in an argon atmosphere and then stirred at 100° C. for 2.5 hours.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure, the concentration residue was dissolved in 5 ml of ethyl acetate and washed with a 5% aqueous potassium dihydrogen phosphate solution twice, and then, the organic layer was washed with 5 ml of a saturated aqueous solution of sodium bicarbonate. The organic layer was dried over anhydrous magnesium sulfate, then filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: ethyl acetate:methanol=100:0 to 86:14 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was dissolved in dichloromethane, n-hexane was added, and then, the deposited solid was collected by filtration and dried under reduced pressure to obtain 71.9 mg of the title compound (yield: 71%) as a white solid.

Mass spectrum (CI, m/z): 436 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.20 & 11.72 (br s, total 1H), 9.56 (br s, 1H), 6.03-5.75 (m, 1H), 4.79 (d, J=4.5 Hz, 1H), 4.48-4.27 (m, 2H), 3.29-3.17 (m, 2H), 2.96-2.85 (m, 1H), 2.56-2.39 (m, 2H), 2.25-2.12 (m, 2H), 1.91-1.72 (m, 2H), 1.68-1.50 (m, 7H), 0.86 (d, J=6.8 Hz, 6H), 0.08 (s, 9H).

(R)—N-(1-Hydroxy-3-phenylpropan-2-yl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. IV-861)

To a solution of 0.102 g (0.232 mmol) of ethyl 5-(chlorocarbonyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 3 and 0.110 g (0.729 mmol) of (R)-2-amino-3-phenylpropan-1-ol in 2.5 ml of dehydrated 1,4-dioxane, 0.20 ml (1.1 mmol) of DIPEA was added at room temperature in an argon atmosphere and then heated and stirred at 100° C. for 1.5 hours. After standing to cool, the resultant was concentrated under reduced pressure, and 4 ml of methanol and 1 ml of triethylamine were added to the residue, applied to a microwave reaction apparatus, and reacted at 80° C. for 1 hour.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure, ethyl acetate was added, the organic layer after washing with a 10% aqueous potassium dihydrogen phosphate solution, a saturated aqueous solution of sodium bicarbonate, and a saturated aqueous solution of sodium chloride in this order was dried over anhydrous magnesium sulfate and filtered, and then, the filtrate was concentrated under reduced pressure. The residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: ethyl acetate:methanol=100:0 to 90:10 (V/V)), a fraction containing the compound of interest was concentrated under reduced pressure, small amounts of dichloromethane and n-hexane were added to the residue, and after ultrasonication, the deposited solid was collected by filtration and dried under reduced pressure to obtain 0.0454 g of the title compound (yield: 40%) as a white solid.

Mass spectrum (CI, m/z): 484 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.19 & 11.65 (br s, total 1H), 9.54 (s, 1H), 7.28-7.18 (m, 4H), 7.18-7.12 (m, 1H), 5.70-5.47 (m, 1H), 4.77 (t, J=5.5 Hz, 1H), 4.45-4.19 (m, 2H), 3.90-3.77 (m, 1H), 3.46-3.29 (m, 2H), 2.87-2.70 (m, 2H), 2.56-2.38 (m, 2H), 2.26-2.11 (m, 2H), 1.92-1.71 (m, 2H), 1.65-1.40 (m, 6H), 0.09 (s, 9H).

(R)—N-(2-Hydroxy-2-phenylethyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. IV-786)

To a solution of 101 mg (0.229 mmol) of ethyl 5-(chlorocarbonyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 3 in 2 ml of dehydrated THF, 0.20 ml (1.1 mmol) of DIPEA and 151 mg (1.10 mmol) of (R)-2-amino-1-phenylethanol were added in this order at room temperature in a nitrogen atmosphere and then stirred for 3 hours then with the temperature unchanged.

After the completion of the reaction, a saturated aqueous solution of sodium bicarbonate was added to the reaction solution and stirred, followed by extraction with dichloromethane three times. All of the organic layers were dried over anhydrous magnesium sulfate, then filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=70:30 to 20:80 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was subjected to preparative HPLC (column: X-Bridge (trade name) ODS, elution solvent: acetonitrile:1 mM aqueous dipotassium hydrogen phosphate solution=40:60 (V/V)), a fraction containing the compound of interest was concentrated under reduced pressure, and acetonitrile was distilled off. The solid deposited in the course of concentration was collected by filtration, washed with pure water, and then dried under reduced pressure to obtain 55 mg of the title compound (yield: 51%) as a white solid.

Mass spectrum (EI, m/z): 469 [M] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.21 & 11.67 (br s, total 1H), 9.56 (s, 1H), 7.36-7.28 (m, 4H), 7.27-7.19 (m, 1H), 6.19-5.94 (m, 1H), 5.59 (d, J=4.0 Hz, 1H), 4.66 (td, J=4.0, 8.0 Hz, 1H), 4.48-4.24 (m, 2H), 3.44-3.22 (m, 1H), 3.09 (ddd, J=4.8, 8.0, 13.2 Hz, 1H), 2.56-2.38 (m, 2H), 2.26-2.12 (m, 2H), 1.90-1.72 (m, 2H), 1.60 (br s, 6H), 0.08 (s, 9H).

(S)—N-(2-Hydroxy-2-phenylethyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. IV-787)

To a solution of 102 mg (0.231 mmol) of ethyl 5-(chlorocarbonyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 3 in 2 ml of dehydrated THF, 0.20 ml (1.1 mmol) of DIPEA and 129 mg (0.943 mmol) of (S)-2-amino-1-phenylethanol were added in this order at room temperature in a nitrogen atmosphere and then stirred for 4 hours with the temperature unchanged.

After the completion of the reaction, a saturated aqueous solution of sodium bicarbonate was added to the reaction solution and stirred, followed by extraction with dichloromethane three times. All of the organic layers were dried over anhydrous magnesium sulfate, then filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: dichloromethane:methanol=100:0 to 98:2 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was subjected to preparative HPLC (column: X-Bridge (trade name) ODS, elution solvent: acetonitrile:1 mM aqueous dipotassium hydrogen phosphate solution=45:55 (V/V)), a fraction containing the compound of interest was concentrated under reduced pressure, and acetonitrile was distilled off. The solid deposited in the course of concentration was collected by filtration, washed with pure water, and then dried under reduced pressure. Ethyl acetate was added to the obtained solid, then insoluble matter was removed by filtration, and the filtrate was concentrated under reduced pressure. The obtained concentration residue was dissolved in ethyl acetate, then n-hexane was added, and the deposited solid was collected by filtration, washed with n-hexane, and then dried under reduced pressure to obtain 52 mg of the title compound (yield: 48%) as a white solid.

Mass spectrum (EI, m/z): 469 [M] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.21 & 11.70 (br s, total 1H), 9.63-9.53 (m, 1H), 7.36-7.28 (m, 4H), 7.27-7.19 (m, 1H), 6.19-5.94 (m, 1H), 5.59 (d, J=4.0 Hz, 1H), 4.66 (td, J=4.0, 8.0 Hz, 1H), 4.48-4.24 (m, 2H), 3.44-3.22 (m, 1H), 3.15-3.04 (m, 1H), 2.56-2.38 (m, 2H), 2.26-2.12 (m, 2H), 1.90-1.72 (m, 2H), 1.60 (br s, 6H), 0.08 (s, 9H).

2-Hydroxy-2-phenylethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxylate (Compound No. IV-670)

To a solution of 0.125 g of 2-[(2-methoxypropan-2-yl)oxy]-2-phenylethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxylate (containing impurities) synthesized in Reference Example 56 in 3 ml of methanol, 0.0077 g (0.031 mmol) of pyridinium p-toluenesulfonate was added at 0° C. in a nitrogen atmosphere and stirred at the same temperature as above for 3.5 hours, and then, 0.020 ml of triethylamine was added and concentrated under reduced pressure.

The residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: 1,2-dichloroethane:ethyl acetate=77:23 to 26:74 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure to obtain 0.0837 g of the title compound (yield: 66% [2 steps]) as a white foam.

Mass spectrum (CI, m/z): 471 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.25 & 12.19 & 11.83 (br s, total 1H), 9.73-9.49 (m, 1H), 7.47-7.19 (m, 5H), 5.58 (d, J=4.5 Hz, 1H), 4.89-4.74 (m, 1H), 4.50-4.23 (m, 2H), 4.21-3.91 (m, 2H), 2.57-2.35 (m, 2H), 2.27-2.09 (m, 2H), 1.93-1.68 (m, 2H), 1.66-1.30 (m, 6H), 0.17-0.01 (m, 9H).

(R)—N-[6,6-Dimethyl-5-(2-phenoxypropanoyl)-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazol-3-yl]-1-(trimethylsilyl)cyclobutanecarboxamide (Compound No. IV-1258)

To a solution of 58.3 mg (0.351 mmol) of (R)-2-phenoxypropanoic acid in 2 ml of dehydrated DMF, 0.12 ml (0.69 mmol) of DIPEA and 152 mg (0.354 mmol) of (1-cyano-2-ethoxy-2-oxoethylideneaminooxy)dimethylaminomorpholinocarbenium hexafluorophosphate [COMU (trade name)] were added in this order at 0° C. in a nitrogen atmosphere and then stirred for 20 minutes with the temperature unchanged. Subsequently, 104 mg (0.274 mmol) of ethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-1(4H)-carboxylate synthesized in the similar manner as in Reference Example 5 was added at 0° C. and then stirred at room temperature for 15.5 hours. Subsequently, 0.10 ml (1.7 mmol) of 2-aminoethanol was added to the reaction solution at room temperature and then stirred for 2.5 hours with the temperature unchanged.

After the completion of the reaction, a saturated aqueous solution of sodium bicarbonate was added to the reaction solution and stirred, followed by extraction with dichloromethane three times. All of the obtained organic layers were dried over anhydrous magnesium sulfate, then filtered, and concentrated under reduced pressure. The operation of adding toluene to the obtained concentration residue, followed by concentration under reduced pressure again was repeated twice, then the resultant was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=75:25 to 50:50 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was dissolved in ethyl acetate, then n-hexane was added, and the deposited solid was collected by filtration, washed with n-hexane, and then dried under reduced pressure to obtain 75 mg of the title compound (yield: 60%) as a white solid.

Mass spectrum (EI, m/z): 454 [M] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.53-11.80 (m, 1H), 9.69 (br s, 1H), 7.30-7.21 (m, 2H), 6.94-6.87 (m, 1H), 6.85-6.78 (m, 2H), 4.90 (q, J=6.5 Hz, 1H), 4.87-4.78 (m, 1H), 4.67-4.57 (m, 1H), 2.56-2.38 (m, 2H), 2.25-2.12 (m, 2H), 1.87-1.74 (m, 2H), 1.67-1.58 (m, 6H), 1.46 (d, J=6.5 Hz, 3H), 0.06 (s, 9H).

(S)—N-[6,6-Dimethyl-5-(2-phenoxypropanoyl)-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazol-3-yl]-1-(trimethylsilyl)cyclobutanecarboxamide (Compound No. IV-1259)

To a solution of 58.6 mg (0.353 mmol) of (S)-2-phenoxypropanoic acid in 2 ml of dehydrated DMF, 0.12 ml (0.69 mmol) of DIPEA and 153 mg (0.356 mmol) of (1-cyano-2-ethoxy-2-oxoethylideneaminooxy)dimethylaminomorpholinocarbenium hexafluorophosphate [COMU (trade name)] were added in this order at 0° C. in a nitrogen atmosphere and then stirred for 20 minutes with the temperature unchanged. Subsequently, 104 mg (0.275 mmol) of ethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-1(4H)-carboxylate synthesized in the similar manner as in Reference Example 5 was added at 0° C. and then stirred at room temperature for 3 hours. Subsequently, 0.10 ml (1.7 mmol) of 2-aminoethanol was added to the reaction solution at room temperature and then stirred for 2 hours with the temperature unchanged.

After the completion of the reaction, a saturated aqueous solution of sodium bicarbonate was added to the reaction solution and stirred, followed by extraction with dichloromethane three times. All of the obtained organic layers were dried over anhydrous magnesium sulfate, then filtered, and concentrated under reduced pressure. The operation of adding toluene to the obtained concentration residue, followed by concentration under reduced pressure again was repeated twice, then the resultant was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=75:25 to 50:50 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was dissolved in ethyl acetate, then n-hexane was added, and the deposited solid was collected by filtration, washed with n-hexane, and then dried under reduced pressure to obtain 75 mg of the title compound (yield: 60%) as a white solid.

Mass spectrum (EI, m/z): 454 [M] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.32 & 11.92 (br s, total 1H), 9.81-9.55 (m, 1H), 7.30-7.21 (m, 2H), 6.94-6.87 (m, 1H), 6.85-6.78 (m, 2H), 4.96-4.74 (m, 2H), 4.71-4.54 (m, 1H), 2.56-2.38 (m, 2H), 2.26-2.10 (m, 2H), 1.91-1.72 (m, 2H), 1.69-1.54 (m, 6H), 1.46 (d, J=6.5 Hz, 3H), 0.06 (br s, 9H).

N-[6,6-Dimethyl-5-(2-phenoxyacetyl)-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazol-3-yl]-1-(trimethylsilyl)cyclobutanecarboxamide (Compound No. IV-1238)

To a solution of 0.143 g (0.279 mmol) of ethyl 6,6-dimethyl-5-(2-phenoxyacetyl)-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 57 in 3 ml of methanol, 0.150 ml (1.38 mmol) of N,N-dimethylethane-1,2-diamine was added at room temperature in a nitrogen atmosphere and then stirred at room temperature for 30 minutes.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure, ethyl acetate was added to the residue, the organic layer after washing with a 10% aqueous potassium dihydrogen phosphate solution, a saturated aqueous solution of sodium bicarbonate, and a saturated aqueous solution of sodium chloride in this order was dried over anhydrous magnesium sulfate and filtered, and then, the filtrate was concentrated under reduced pressure. The residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: 1,2-dichloroethane:ethyl acetate=100:0 to 62:38 (V/V)), a fraction containing the compound of interest was concentrated under reduced pressure, the residue was dissolved in a small amount of dichloromethane, and after addition of n-hexane and ultrasonication, the deposited solid was collected by filtration and dried under reduced pressure to obtain 0.0876 g of the title compound (yield: 71%) as a white solid.

Mass spectrum (CI, m/z): 441 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.29 & 11.89 (br s, total 1H), 9.84-9.56 (m, 1H), 7.30-7.24 (m, 2H), 6.95-6.89 (m, 3H), 4.78 (s, 2H), 4.73-4.56 (m, 2H), 2.56-2.35 (m, 2H), 2.27-2.08 (m, 2H), 1.93-1.54 (m, 8H), 0.08 (s, 9H).

(R)—N-[6,6-Dimethyl-5-(2-phenoxypropanoyl)-1,4,5,6-tetrahydropyrrol o[3,4-c]pyrazol-3-yl]-1-(trimethylsilyl)cyclopropanecarboxamide (Compound No. III-1140)

To a solution of 143 mg (0.861 mmol) of (R)-2-phenoxypropanoic acid in 3 ml of dehydrated dichloromethane, 0.12 ml (1.4 mmol) of oxalyl chloride and 0.0050 ml (0.065 mmol) of dehydrated DMF were added in this order at 0° C. in a nitrogen atmosphere and then stirred for 2 hours with the temperature unchanged.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure to obtain a concentration residue.

To a solution of 154 mg (0.424 mmol) of ethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclopropanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 46 and 0.38 ml (2.2 mmol) of DIPEA in 2 ml of dehydrated dichloromethane, a solution of the obtained concentration residue in 1 ml of dehydrated dichloromethane was added at 0° C. in a nitrogen atmosphere and then stirred for 1.5 hours with the temperature unchanged. Subsequently, 0.24 ml (2.2 mmol) of N,N-dimethylethane-1,2-diamine was added to the reaction solution at 0° C. and then stirred at room temperature for 2 hours.

After the completion of the reaction, the reaction solution diluted with dichloromethane was washed with a 5% aqueous potassium bisulfate solution and then separated into an aqueous layer and an organic layer. The aqueous layer was subjected to extraction with dichloromethane twice, and then, all of the obtained organic layers were dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=80:20 to 50:50 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was dissolved in ethyl acetate, then n-hexane was added, and the deposited solid was collected by filtration, washed with n-hexane, and then dried under reduced pressure to obtain 155 mg of the title compound (yield: 83%) as a white solid.

Mass spectrum (CI, m/z): 441 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.33 & 12.02 (br s, total 1H), 10.03-9.76 (m, 1H), 7.30-7.22 (m, 2H), 6.94-6.87 (m, 1H), 6.85-6.78 (m, 2H), 4.95-4.70 (m, 2H), 4.67-4.51 (m, 1H), 1.70-1.52 (m, 6H), 1.45 (d, J=6.4 Hz, 3H), 0.98 (br s, 2H), 0.80-0.59 (m, 2H), 0.01 (br s, 9H).

N-{5-[3-(Benzyloxy)-2-phenoxypropanoyl]-6,6-dimethyl-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazol-3-yl}-1-(trimethylsilyl)cyclobutanecarboxamide (Compound No. IV-1354)

To a solution of 340 mg of 3-(benzyloxy)-2-phenoxypropanoic acid (containing impurities) synthesized in the similar manner as in Reference Example 60 in 3 ml of dehydrated dichloromethane, 0.005 ml (0.07 mmol) of DMF and 0.140 ml (1.63 mmol) of oxalyl chloride were added dropwise with stirring at 0° C. in an argon atmosphere and stirred at the same temperature as above for 2 hours.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure to obtain a concentration residue.

To a solution of 236 mg (0.625 mmol) of ethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 84 and 0.550 ml (3.16 mmol) of DIPEA in 3 ml of dehydrated dichloromethane, a solution of the obtained concentration residue in 1 ml of dehydrated dichloromethane was added dropwise with stirring at 0° C. in an argon atmosphere and stirred at the same temperature as above for 1 hour. Subsequently, 0.340 ml (3.12 mmol) of N,N-dimethylethane-1,2-diamine was added to the reaction solution at room temperature and then reacted with stirring at room temperature for 16 hours.

After the completion of the reaction, a saturated aqueous solution of sodium bicarbonate was added to the reaction solution, followed by extraction with dichloromethane. The obtained organic layer was washed with a saturated aqueous solution of sodium chloride, then dried over anhydrous sodium sulfate, and filtered, and the filtrate was concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=60:40 to 30:70 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was subjected again to silica gel column chromatography (DNH silica gel, elution solvent: 1,2-dichloroethane:methanol=100:0 to 90:10), and some fractions containing the compound of interest at high purity were concentrated under reduced pressure. The obtained concentration residue was dissolved by adding methanol and then added to water, and the deposited solid was collected by filtration and dried under reduced pressure to obtain 11.7 mg of the title compound (yield: 3.3%) as a white solid. Also, the remaining fractions containing the compound of interest obtained by silica gel column chromatography were combined, concentrated under reduced pressure, and dried under reduced pressure to obtain 162 mg of the title compound (yield: 46%) as a white solid.

Mass spectrum (CI, m/z): 561 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.30 & 11.92 (br s, total 1H), 9.82-9.54 (m, 1H), 7.38-7.20 (m, 7H), 6.97-6.88 (m, 1H), 6.88-6.80 (m, 2H), 5.03-4.66 (m, 3H), 4.60 (s, 2H), 3.93-3.81 (m, 2H), 2.57-2.39 (m, 2H), 2.29-2.11 (m, 2H), 1.91-1.71 (m, 2H), 1.70-1.50 (m, 6H), 0.07 (s, 9H).

N-[5-(3-Hydroxy-2-phenoxypropanoyl)-6,6-dimethyl-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazol-3-yl]-1-(trimethylsilyl)cyclobutanecarboxamide (Compound No. IV-1330)

To a solution of 162 mg (0.289 mmol) of N-{5-[3-(benzyloxy)-2-phenoxypropanoyl]-6,6-dimethyl-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazol-3-yl}-1-(trimethylsilyl)cyclobutanecarboxamide synthesized in the similar manner as in Example 72 in 5 ml of ethanol, 30 mg of 20% palladium hydroxide/carbon (containing 50 wt % water) was added in an argon atmosphere and after replacement with a hydrogen atmosphere under reduced pressure, stirred at room temperature for 5 hours.

After the completion of the reaction, replacement with an argon atmosphere was performed, and the reaction solution was filtered through celite. The solid on the celite was washed with ethanol, and all of the filtrates were concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (elution solvent: 1,2-dichloroethane:methanol=100:0 to 95:5 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was dissolved by adding methanol and then added to water, and the deposited solid was collected by filtration and dried under reduced pressure to obtain 61 mg of the title compound (yield: 45%) as a white solid.

Mass spectrum (CI, m/z): 471 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.39-11.82 (m, 1H), 9.70 (br s, 1H), 7.32-7.22 (m, 2H), 6.95-6.88 (m, 1H), 6.85-6.78 (m, 2H), 5.34-5.23 (m, 1H), 4.92-4.82 (m, 1H), 4.81-4.69 (m, 2H), 3.85-3.71 (m, 2H), 2.60-2.39 (m, 2H), 2.26-2.12 (m, 2H), 1.89-1.71 (m, 2H), 1.62 (s, 3H), 1.60 (s, 3H), 0.08 (s, 9H).

N-{5-[2-(4-Chlorophenoxy)propanoyl]-6,6-dimethyl-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazol-3-yl}-1-(trimethylsilyl)cyclobutanecarboxamide (Compound No. IV-1270)

To a solution of 150 mg (0.748 mmol) of 2-(4-chlorophenoxy)propanoic acid [purchased from AK Scientific, Inc.] in 3 ml of dehydrated dichloromethane, 0.080 ml (0.93 mmol) of oxalyl chloride and 0.004 ml (0.05 mmol) of DMF were added dropwise with stirring at 0° C. in an argon atmosphere and stirred at the same temperature as above for 2 hours.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure to obtain a concentration residue.

To a solution of 129 mg (0.341 mmol) of ethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 84 and 0.300 ml (1.72 mmol) of DIPEA in 3 ml of dehydrated dichloromethane, a solution of the obtained concentration residue in 1 ml of dehydrated dichloromethane was added dropwise with stirring at 0° C. in an argon atmosphere and stirred at the same temperature as above for 3 hours. Subsequently, 0.200 ml (1.84 mmol) of N,N-dimethylethane-1,2-diamine was added to the reaction solution at room temperature and then reacted with stirring at room temperature for 16 hours.

After the completion of the reaction, a saturated aqueous solution of sodium bicarbonate was added to the reaction solution, followed by extraction with dichloromethane. The obtained organic layer was washed with a saturated aqueous solution of sodium chloride, then dried over anhydrous sodium sulfate, and filtered, and the filtrate was concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=60:40 to 30:70 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was dissolved by adding methanol and then added to water, and the deposited solid was collected by filtration and dried under reduced pressure to obtain a solid. The obtained solid was subjected again to silica gel column chromatography (DNH silica gel, elution solvent: n-hexane:ethyl acetate=50:50 to 0:100 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was dissolved by adding methanol and then added to water, and the deposited solid was collected by filtration and dried under reduced pressure to obtain 39 mg of the title compound (yield: 23%) as a white solid.

Mass spectrum (CI, m/z): 489 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.32 & 11.89 (br s, total 1H), 9.79-9.53 (m, 1H), 7.34-7.24 (m, 2H), 6.90-6.77 (m, 2H), 4.93 (q, J=6.4 Hz, 1H), 4.90-4.72 (m, 1H), 4.70-4.50 (m, 1H), 2.60-2.36 (m, 2H), 2.28-2.10 (m, 2H), 1.93-1.70 (m, 2H), 1.70-1.53 (m, 6H), 1.46 (d, J=6.4 Hz, 3H), 0.06 (s, 9H).

N-{5-[2-(2-Chlorophenoxy)propanoyl]-6,6-dimethyl-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazol-3-yl}-1-(trimethylsilyl)cyclobutanecarboxamide (Compound No. IV-1266)

To a solution of 150 mg (0.748 mmol) of 2-(2-chlorophenoxy)propanoic acid in 3 ml of dehydrated dichloromethane, 0.080 ml (0.93 mmol) of oxalyl chloride and 0.004 ml (0.05 mmol) of DMF were added dropwise with stirring at 0° C. in an argon atmosphere and stirred at the same temperature as above for 2 hours.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure to obtain a concentration residue.

To a solution of 129 mg (0.341 mmol) of ethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 84 and 0.300 ml (1.72 mmol) of DIPEA in 3 ml of dehydrated dichloromethane, a solution of the obtained concentration residue in 1 ml of dehydrated dichloromethane was added dropwise with stirring at 0° C. in an argon atmosphere and stirred at the same temperature as above for 3 hours. Subsequently, 0.200 ml (1.84 mmol) of N,N-dimethylethane-1,2-diamine was added to the reaction solution at room temperature and then reacted with stirring at room temperature for 16 hours.

After the completion of the reaction, a saturated aqueous solution of sodium bicarbonate was added to the reaction solution, followed by extraction with dichloromethane. The obtained organic layer was washed with a saturated aqueous solution of sodium chloride, then dried over anhydrous sodium sulfate, and filtered, and the filtrate was concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=60:40 to 30:70 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was dissolved by adding methanol and then added to water, and the deposited solid was collected by filtration and dried under reduced pressure to obtain a solid. The obtained solid was subjected again to silica gel column chromatography (DNH silica gel, elution solvent: n-hexane:ethyl acetate=100:0 to 0:100 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was dissolved by adding methanol and then added to water, and the deposited solid was collected by filtration and dried under reduced pressure to obtain 16 mg of the title compound (yield: 10%) as a white solid.

Mass spectrum (CI, m/z): 489 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.32 & 11.92 (br s, total 1H), 9.80-9.54 (m, 1H), 7.45-7.38 (m, 1H), 7.29-7.20 (m, 1H), 6.96-6.89 (m, 1H), 6.89-6.83 (m, 1H), 5.01 (q, J=6.5 Hz, 1H), 4.92-4.74 (m, 1H), 4.72-4.52 (m, 1H), 2.58-2.37 (m, 2H), 2.27-2.10 (m, 2H), 1.93-1.71 (m, 2H), 1.71-1.55 (m, 6H), 1.51 (d, J=6.5 Hz, 3H), 0.06 (s, 9H).

N-{5-[2-(Cyclohexyloxy)propanoyl]-6,6-dimethyl-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazol-3-yl}-1-(trimethylsilyl)cyclobutanecarboxamide (Compound No. IV-1255)

To a solution of 120 mg (0.697 mmol) of 2-(cyclohexyloxy)propanoic acid [purchased from Enamine Ltd.] in 3 ml of dehydrated dichloromethane, 0.080 ml (0.93 mmol) of oxalyl chloride and 0.005 ml (0.07 mmol) of DMF were added dropwise with stirring at 0° C. in an argon atmosphere and stirred at the same temperature as above for 2 hours.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure to obtain a concentration residue.

To a solution of 129 mg (0.341 mmol) of ethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 84 and 0.300 ml (1.72 mmol) of DIPEA in 3 ml of dehydrated dichloromethane, a solution of the obtained concentration residue in 1 ml of dehydrated dichloromethane was added dropwise with stirring at 0° C. in an argon atmosphere and stirred at the same temperature as above for 2 hours. Subsequently, 0.200 ml (1.84 mmol) of N,N-dimethylethane-1,2-diamine was added to the reaction solution at room temperature and then reacted with stirring at room temperature for 16 hours.

After the completion of the reaction, a saturated aqueous solution of sodium bicarbonate was added to the reaction solution, followed by extraction with dichloromethane. The obtained organic layer was washed with a saturated aqueous solution of sodium chloride, then dried over anhydrous sodium sulfate, and filtered, and the filtrate was concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=60:40 to 30:70 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was dissolved by adding methanol and then added to water, and the deposited solid was collected by filtration and dried under reduced pressure to obtain 37 mg of the title compound (yield: 24%) as a white solid.

Mass spectrum (CI, m/z): 461 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.39-11.73 (m, 1H), 9.63 (br s, 1H), 4.78-4.55 (m, 2H), 4.23 (q, J=6.5 Hz, 1H), 3.41-3.26 (m, 1H), 2.58-2.37 (m, 2H), 2.25-2.12 (m, 2H), 1.90-1.72 (m, 4H), 1.71-1.55 (m, 8H), 1.50-1.39 (m, 1H), 1.28-1.05 (m, 8H), 0.07 (s, 9H).

N-{5-[2-(3-Chlorophenoxy)propanoyl]-6,6-dimethyl-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazol-3-yl}-1-(trimethylsilyl)cyclobutanecarboxamide (Compound No. IV-1268)

To a solution of 150 mg (0.748 mmol) of 2-(3-chlorophenoxy)propanoic acid [purchased from Combi-Blocks Inc.] in 3 ml of dehydrated dichloromethane, 0.080 ml (0.93 mmol) of oxalyl chloride and 0.005 ml (0.07 mmol) of DMF were added dropwise with stirring at 0° C. in an argon atmosphere and stirred at the same temperature as above for 2 hours.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure to obtain a concentration residue.

To a solution of 129 mg (0.341 mmol) of ethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 84 and 0.300 ml (1.72 mmol) of DIPEA in 3 ml of dehydrated dichloromethane, a solution of the obtained concentration residue in 1 ml of dehydrated dichloromethane was added dropwise with stirring at 0° C. in an argon atmosphere and stirred at the same temperature as above for 2 hours. Subsequently, 0.200 ml (1.84 mmol) of N,N-dimethylethane-1,2-diamine was added to the reaction solution at room temperature and then reacted with stirring at room temperature for 16 hours.

After the completion of the reaction, a saturated aqueous solution of sodium bicarbonate was added to the reaction solution, followed by extraction with dichloromethane. The obtained organic layer was washed with a saturated aqueous solution of sodium chloride, then dried over anhydrous sodium sulfate, and filtered, and the filtrate was concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=60:40 to 30:70 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was dissolved by adding methanol and then added to water, and the deposited solid was collected by filtration and dried under reduced pressure. The obtained solid was subjected again to silica gel column chromatography (DNH silica gel, elution solvent: n-hexane:ethyl acetate=100:0 to 0:100 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was dissolved by adding methanol and then added to water, and the deposited solid was collected by filtration and dried under reduced pressure to obtain 30 mg of the title compound (yield: 18%) as a white solid.

Mass spectrum (CI, m/z): 489 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.32 & 11.93 (br s, total 1H), 9.79-9.56 (m, 1H), 7.29 (t, J=8.3 Hz, 1H), 7.00-6.94 (m, 1H), 6.86 (t, J=2.1 Hz, 1H), 6.83-6.77 (m, 1H), 5.00 (q, J=6.4 Hz, 1H), 4.90-4.73 (m, 1H), 4.71-4.51 (m, 1H), 2.57-2.37 (m, 2H), 2.27-2.10 (m, 2H), 1.92-1.71 (m, 2H), 1.70-1.53 (m, 6H), 1.47 (d, J=6.4 Hz, 3H), 0.06 (s, 9H).

N-[5-(2-Methoxypropanoyl)-6,6-dimethyl-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazol-3-yl]-1-(trimethylsilyl)cyclobutanecarboxamide (Compound No. IV-1241)

To a solution of 65.0 mg (0.624 mmol) of 2-methoxypropanoic acid [purchased from Combi-Blocks Inc.] in 3 ml of dehydrated dichloromethane, 0.200 ml (1.15 mmol) of DIPEA and 220 mg (0.514 mmol) of (1-cyano-2-ethoxy-2-oxoethylideneaminooxy)dimethylaminomorpholinocarbenium hexafluorophosphate [COMU (trade name)] were added in this order with stirring at 0° C. in an argon atmosphere and then stirred at the same temperature as above for 15 minutes. Subsequently, 129 mg (0.341 mmol) of ethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 84 was added at 0° C. and stirred at room temperature for 16 hours. Subsequently, 0.220 ml (2.02 mmol) of N,N-dimethylethane-1,2-diamine was added to the reaction solution at room temperature and then reacted with stirring at room temperature for 4 hours.

The reaction solution was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=60:40 to 30:70 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure to obtain 61 mg of the title compound (yield: 46%) as a white solid.

Mass spectrum (CI, m/z): 393 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.28 & 11.86 (br s, total 1H), 9.80-9.53 (m, 1H), 4.82-4.44 (m, 2H), 4.06 (q, J=6.4 Hz, 1H), 3.20 (s, 3H), 2.57-2.37 (m, 2H), 2.29-2.10 (m, 2H), 1.93-1.55 (m, 8H), 1.21 (d, J=6.4 Hz, 3H), 0.08 (s, 9H).

N-[5-(3-Methoxy-2-phenoxypropanoyl)-6,6-dimethyl-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazol-3-yl]-1-(trimethylsilyl)cyclobutanecarboxamide (Compound No. IV-1348)

To a solution of 116 mg of 3-methoxy-2-phenoxypropanoic acid (containing impurities) synthesized in the similar manner as in Reference Example 63 in 3 ml of dehydrated dichloromethane, 0.004 ml (0.05 mmol) of DMF and 0.070 ml (0.82 mmol) of oxalyl chloride were added dropwise with stirring at 0° C. in an argon atmosphere and stirred at the same temperature as above for 2 hours.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure to obtain a concentration residue.

To a solution of 124 mg (0.329 mmol) of ethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 84 and 0.300 ml (1.72 mmol) of DIPEA in 3 ml of dehydrated dichloromethane, a solution of the obtained concentration residue in 1 ml of dehydrated dichloromethane was added dropwise with stirring at 0° C. in an argon atmosphere and stirred at the same temperature as above for 2 hours. Subsequently, 0.200 ml (1.84 mmol) of N,N-dimethylethane-1,2-diamine was added to the reaction solution at room temperature and then reacted with stirring at room temperature for 16 hours.

The reaction solution was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=60:40 to 30:70 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was dissolved by adding methanol and then added to water, and the deposited solid was collected by filtration and dried under reduced pressure to obtain 75 mg of the title compound (yield: 47%) as a white solid.

Mass spectrum (CI, m/z): 485 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.32 & 11.94 (br s, total 1H), 9.85-9.57 (m, 1H), 7.34-7.21 (m, 2H), 6.97-6.89 (m, 1H), 6.88-6.78 (m, 2H), 4.98-4.79 (m, 2H), 4.78-4.59 (m, 1H), 3.83-3.68 (m, 2H), 3.34 (s, 3H), 2.58-2.37 (m, 2H), 2.28-2.10 (m, 2H), 1.92-1.71 (m, 2H), 1.69-1.49 (m, 6H), 0.08 (s, 9H).

N-{6,6-Dimethyl-5-[2-(pyridin-3-yloxy)propanoyl]-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazol-3-yl}-1-(trimethylsilyl)cyclobutanecarboxamide (Compound No. IV-1274)

To a solution of 114 mg (0.682 mmol) of 2-(pyridin-3-yloxy)propanoic acid [purchased from Enamine Ltd.] in 3 ml of dehydrated dichloromethane, 0.200 ml (1.15 mmol) of DIPEA and 250 mg (0.584 mmol) of (1-cyano-2-ethoxy-2-oxoethylideneaminooxy)dimethylaminomorpholinocarbenium hexafluorophosphate [COMU (trade name)] were added in this order with stirring at 0° C. in an argon atmosphere and then stirred at the same temperature as above for 15 minutes. Subsequently, 172 mg (0.454 mmol) of ethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 84 was added at 0° C. and stirred at room temperature for 16 hours. Subsequently, 0.250 ml (2.30 mmol) of N,N-dimethylethane-1,2-diamine was added to the reaction solution at room temperature and then reacted with stirring at room temperature for 4 hours.

The reaction solution was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=60:40 to 30:70 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was dissolved by adding methanol and then added to water, and the deposited solid was collected by filtration and dried under reduced pressure to obtain 89 mg of the title compound (yield: 43%) as a white solid.

Mass spectrum (CI, m/z): 456 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.32 & 11.88 (s, total 1H), 9.76-9.60 (m, 1H), 8.24-8.17 (m, 1H), 8.17-8.09 (m, 1H), 7.33-7.27 (m, 1H), 7.25-7.20 (m, 1H), 5.06 (q, J=6.3 Hz, 1H), 4.93-4.79 (m, 1H), 4.70-4.54 (m, 1H), 2.57-2.38 (m, 2H), 2.27-2.13 (m, 2H), 1.91-1.71 (m, 2H), 1.69-1.54 (m, 6H), 1.50 (d, J=6.3 Hz, 3H), 0.13-0.02 (m, 9H).

N-{5-[3-(Dimethylamino)-2-phenoxypropanoyl]-6,6-dimethyl-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazol-3-yl}-1-(trimethylsilyl)cyclobutanecarboxamide (Compound No. IV-1372)

To a solution of 70.0 mg (0.335 mmol) of 3-(dimethylamino)-2-phenoxypropanoic acid synthesized in the similar manner as in Reference Example 66 in 3 ml of dehydrated DMF, 0.150 ml (0.861 mmol) of DIPEA and 200 mg (0.467 mmol) of (1-cyano-2-ethoxy-2-oxoethylideneaminooxy)dimethylaminomorpholinocarbenium hexafluorophosphate [COMU (trade name)] were added in this order with stirring at 0° C. in an argon atmosphere and then stirred at the same temperature as above for 15 minutes. Subsequently, 115 mg (0.304 mmol) of ethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 84 was added at 0° C. and stirred at room temperature for 3 hours. Subsequently, 0.200 ml (1.84 mmol) of N,N-dimethylethane-1,2-diamine was added to the reaction solution at room temperature and then reacted with stirring at room temperature for 16 hours.

After the completion of the reaction, a saturated aqueous solution of sodium bicarbonate was added to the reaction solution, followed by extraction with dichloromethane. The obtained organic layer was washed with a saturated aqueous solution of sodium chloride, then dried over anhydrous sodium sulfate, and filtered, and the filtrate was concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (elution solvent: 1,2-dichloroethane:methanol=100:0 to 90:10 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was dissolved by adding methanol and then added to water, and the deposited solid was collected by filtration and dried under reduced pressure to obtain 57 mg of the title compound (yield: 38%) as a white solid.

Mass spectrum (CI, m/z): 498 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.48-11.69 (m, 1H), 9.67 (br s, 1H), 7.32-7.23 (m, 2H), 6.96-6.88 (m, 1H), 6.84-6.77 (m, 2H), 4.87 (br d, J=12.0 Hz, 1H), 4.81 (dd, J=4.5, 6.6 Hz, 1H), 4.66 (br d, J=12.0 Hz, 1H), 2.82-2.70 (m, 2H), 2.57-2.39 (m, 2H), 2.26 (s, 6H), 2.24-2.12 (m, 2H), 1.89-1.73 (m, 2H), 1.62 (s, 3H), 1.61 (s, 3H), 0.07 (s, 9H).

N-[6,6-Dimethyl-5-(2-phenoxy-2-phenylacetyl)-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazol-3-yl]-1-(trimethylsilyl)cyclobutanecarboxamide (Compound No. IV-1211)

To a solution of 140 mg (0.613 mmol) of 2-phenoxy-2-phenylacetic acid [purchased from Enamine Ltd.] in 3 ml of dehydrated dichloromethane, 0.080 ml (0.93 mmol) of oxalyl chloride and 0.005 ml (0.07 mmol) of DMF were added dropwise with stirring at 0° C. in an argon atmosphere and stirred at the same temperature as above for 2 hours.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure to obtain a concentration residue.

To a solution of 129 mg (0.341 mmol) of ethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 84 and 0.300 ml (1.72 mmol) of DIPEA in 3 ml of dehydrated dichloromethane, a solution of the obtained concentration residue in 1 ml of dehydrated dichloromethane was added dropwise with stirring at 0° C. in an argon atmosphere and stirred at the same temperature as above for 3 hours. Subsequently, 0.200 ml (1.84 mmol) of N,N-dimethylethane-1,2-diamine was added to the reaction solution at room temperature and then reacted with stirring at room temperature for 16 hours.

The reaction solution was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=60:40 to 30:70 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was dissolved by adding methanol and then added to water, and the deposited solid was collected by filtration and dried under reduced pressure to obtain 94 mg of the title compound (yield: 53%) as a white solid.

Mass spectrum (CI, m/z): 517 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.30 & 11.91 (br s, total 1H), 9.57 (br s, 1H), 7.57-7.50 (m, 2H), 7.48-7.36 (m, 3H), 7.31-7.23 (m, 2H), 6.97-6.88 (m, 3H), 5.91 (s, 1H), 4.98-4.72 (m, 1H), 4.40-4.21 (m, 1H), 2.48-2.35 (m, 2H), 2.27-2.08 (m, 2H), 1.91-1.73 (m, 2H), 1.67 (s, 3H), 1.60 (s, 3H), 0.04 (s, 9H).

N-{5-[3-(3,3-Difluoropyrrolidin-1-yl)-2-phenoxypropanoyl]-6,6-dimeth yl-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazol-3-yl}-1-(trimethylsilyl)cyclobutanecarboxamide (Compound No. IV-1378)

To a solution of 170 mg of 3-(3,3-difluoropyrrolidin-1-yl)-2-phenoxypropanoic acid (containing impurities) synthesized in the similar manner as in Reference Example 69 in 3 ml of dehydrated DMF, 0.250 ml (1.44 mmol) of DIPEA and 300 mg (0.700 mmol) of (1-cyano-2-ethoxy-2-oxoethylideneaminooxy)dimethylaminomorpholinocarbenium hexafluorophosphate [COMU (trade name)] were added in this order with stirring at 0° C. in an argon atmosphere and then stirred at the same temperature as above for 15 minutes. Subsequently, 129 mg (0.341 mmol) of ethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 84 was added at 0° C. and stirred at room temperature for 16 hours. Subsequently, 0.200 ml (1.84 mmol) of N,N-dimethylethane-1,2-diamine was added to the reaction solution at room temperature and then reacted with stirring at room temperature for 64 hours.

The reaction solution was subjected to silica gel column chromatography (elution solvent: 1,2-dichloroethane:methanol=100:0 to 90:10 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was subjected to preparative HPLC (column: X-Bridge (trade name) ODS, elution solvent: acetonitrile:1 mM aqueous potassium dihydrogen phosphate solution=50:50 (V/V)), and ethyl acetate and water were added to a fraction containing the compound of interest, then an organic layer and an aqueous layer were separated. The obtained organic layer was concentrated under reduced pressure. The obtained concentration residue was dissolved by adding methanol and then added to water, and the deposited solid was collected by filtration and dried under reduced pressure to obtain 49 mg of the title compound (yield: 26%) as a white solid.

Mass spectrum (CI, m/z): 560 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.32 & 11.94 (br s, total 1H), 9.84-9.59 (m, 1H), 7.32-7.23 (m, 2H), 6.97-6.89 (m, 1H), 6.85-6.78 (m, 2H), 4.97-4.80 (m, 2H), 4.74-4.57 (m, 1H), 3.14-2.80 (m, 6H), 2.58-2.37 (m, 2H), 2.29-2.10 (m, 4H), 1.92-1.72 (m, 2H), 1.70-1.52 (m, 6H), 0.14-0.03 (m, 9H).

N-[5-(3-Hydroxy-2-phenylpropanoyl)-6,6-dimethyl-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazol-3-yl]-1-(trimethylsilyl)cyclobutanecarboxamide (Compound No. IV-632)

To a solution of 139 mg (0.540 mmol) of 3-(benzyloxy)-2-phenylpropanoic acid synthesized according to the method described in Tetrahedron Lett., 2002 (43), 9691-9693] in 3 ml of dehydrated DMF, 0.18 ml (1.0 mmol) of DIPEA and 233 mg (0.544 mmol) of (1-cyano-2-ethoxy-2-oxoethylideneaminooxy)dimethylaminomorpholinocarbenium hexafluorophosphate [COMU (trade name)] were added in this order at 0° C. in a nitrogen atmosphere and then stirred for 15 minutes with the temperature unchanged. Subsequently, 158 mg (0.418 mmol) of ethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-1(4H)-carboxylate synthesized in the similar manner as in Reference Example 5 was added at 0° C. and then stirred at room temperature for 3.5 hours.

After the completion of the reaction, a saturated aqueous solution of sodium bicarbonate was added to the reaction solution and stirred, followed by extraction with ethyl acetate three times. All of the obtained organic layers were dried over anhydrous magnesium sulfate, then filtered, and concentrated under reduced pressure to obtain a concentration residue.

To a solution of the obtained concentration residue in 4 ml of THF, 0.25 ml (1.8 mmol) of triethylamine and 0.10 ml (1.7 mmol) of 2-aminoethanol were added in this order at room temperature in a nitrogen atmosphere and then stirred for 1.5 hours with the temperature unchanged.

After the completion of the reaction, a saturated aqueous solution of sodium bicarbonate was added to the reaction solution and stirred, followed by extraction with dichloromethane three times. All of the obtained organic layers were dried over anhydrous magnesium sulfate, then filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=70:30 to 50:50 (V/V)), subsequently concentrated under reduced pressure, and dried under reduced pressure to obtain a concentration residue.

To a solution of the obtained concentration residue in 2 ml of ethanol, 25.4 mg of 20% palladium hydroxide/carbon [containing 50 wt % water] was added at room temperature in a nitrogen atmosphere and then, after replacement with a hydrogen atmosphere under reduced pressure, stirred at room temperature for 1.5 hours. The inside of the reaction container was replaced with a nitrogen atmosphere under reduced pressure, and subsequently, 68.3 mg of 20% palladium hydroxide/carbon [containing 50 wt % water] was added at room temperature and then, after replacement with a hydrogen atmosphere again under reduced pressure, stirred at room temperature for 3.5 hours.

After the completion of the reaction, the inside of the reaction container was replaced with a nitrogen atmosphere under reduced pressure. The reaction solution was filtered using a celite filter, subsequently the removed solid was washed with ethanol, and then, the filtrate was concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=70:30 to 30:70 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was dissolved in ethyl acetate, then n-hexane was added, and the deposited solid was collected by filtration, washed with n-hexane, and then dried under reduced pressure to obtain 104 mg of the title compound (yield: 55% [2 steps]) as a white solid.

Mass spectrum (EI, m/z): 454 [M] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.45-11.70 (m, 1H), 9.58 (br s, 1H), 7.35-7.20 (m, 5H), 4.81-4.64 (m, 2H), 4.23 (d, J=12.0 Hz, 1H), 3.98-3.89 (m, 1H), 3.84 (dd, J=5.4, 8.2 Hz, 1H), 3.52-3.44 (m, 1H), 2.58-2.37 (m, 2H), 2.24-2.12 (m, 2H), 1.87-1.73 (m, 2H), 1.69 (s, 3H), 1.58 (s, 3H), 0.05 (s, 9H).

(S)—N-[5-(3-Hydroxy-2-phenylpropanoyl)-6,6-dimethyl-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazol-3-yl]-1-(trimethylsilyl)cyclobutanecarboxamide (Compound No. IV-633)

To a solution of 139 mg (0.256 mmol) of (S)—N-{5-[3-(benzyloxy)-2-phenylpropanoyl]-6,6-dimethyl-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazol-3-yl}-1-(trimethylsilyl)cyclobutanecarboxamide synthesized in the similar manner as in Reference Example 70 in 2 ml of ethanol, 58.4 mg of 20% palladium hydroxide/carbon [containing 50 wt % water] was added at room temperature in a nitrogen atmosphere and then, after replacement with a hydrogen atmosphere under reduced pressure, stirred at room temperature for 3 hours.

After the completion of the reaction, the inside of the reaction container was replaced with a nitrogen atmosphere under reduced pressure. The reaction solution was filtered using a celite filter, subsequently the removed solid was washed with ethyl acetate, and then, the filtrate was concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=85:15 to 35:65 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was dissolved in ethyl acetate, then n-hexane was added, and the deposited solid was collected by filtration, washed with n-hexane, and then dried under reduced pressure to obtain 55 mg of the title compound (yield: 47%) as a white solid.

Mass spectrum (CI, m/z): 455 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.24 & 11.85 (br s, total 1H), 9.73-9.44 (m, 1H), 7.35-7.20 (m, 5H), 4.81-4.63 (m, 2H), 4.33-4.11 (m, 1H), 3.98-3.89 (m, 1H), 3.88-3.80 (m, 1H), 3.52-3.44 (m, 1H), 2.60-2.36 (m, 2H), 2.26-2.10 (m, 2H), 1.89-1.64 (m, 5H), 1.58 (br s, 3H), 0.05 (s, 9H).

(R)—N-{5-[3-(Benzyloxy)-2-phenylpropanoyl]-6,6-dimethyl-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazol-3-yl}-1-(trimethylsilyl)cyclobutanecarboxamide (Compound No. IV-1221)

To a solution of 1.22 g (4.76 mmol) of (R)-3-(benzyloxy)-2-phenylpropanoic acid [synthesized according to the method described in Tetrahedron Lett., 2002, 43, 9691-9693] in 20 ml of dehydrated dichloromethane, 0.55 ml (6.4 mmol) of oxalyl chloride and 0.030 ml (0.39 mmol) of dehydrated DMF were added in this order at 0° C. in a nitrogen atmosphere and then stirred for 2 hours with the temperature unchanged.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure to obtain a concentration residue.

To a solution of 903 mg (2.39 mmol) of ethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 84 and 1.70 ml (9.76 mmol) of DIPEA in 15 ml of dehydrated dichloromethane, a solution of the obtained concentration residue in 5 ml of dehydrated dichloromethane was added at 0° C. in a nitrogen atmosphere and then stirred for 2 hours with the temperature unchanged. Subsequently, 1.0 ml (9.2 mmol) of N,N-dimethylethane-1,2-diamine was added to the reaction solution at 0° C. and then stirred at room temperature for 1.5 hours.

After the completion of the reaction, the reaction solution diluted with dichloromethane was washed with a 5% aqueous potassium bisulfate solution and then the aqueous layer and the organic layer were separated. The aqueous layer was subjected to extraction with dichloromethane twice, and then, all of the obtained organic layers were dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=85:15 to 50:50 (V/V)), and some fractions containing the compound of interest at high purity were concentrated under reduced pressure. The obtained concentration residue was dissolved in ethyl acetate, then n-hexane was added, and the deposited solid was collected by filtration, washed with n-hexane, and then dried under reduced pressure to obtain 43 mg of the title compound (yield: 3%) as a white solid. Also, the remaining fractions containing the compound of interest obtained by silica gel column chromatography were concentrated under reduced pressure and dried under reduced pressure to obtain 1.10 g of the title compound (yield: 85%) as a pale yellow foam.

Mass spectrum (CI, m/z): 545 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.25 & 11.85 (s, total 1H), 9.65-9.47 (m, 1H), 7.38-7.20 (m, 10H), 4.79-4.62 (m, 1H), 4.52 (d, J=12.6 Hz, 1H), 4.47 (d, J=12.6 Hz, 1H), 4.31-4.15 (m, 1H), 4.07-3.94 (m, 2H), 3.57-3.47 (m, 1H), 2.57-2.36 (m, 2H), 2.25-2.09 (m, 2H), 1.89-1.64 (m, 5H), 1.63-1.50 (m, 3H), 0.09-0.02 (m, 9H).

(R)—N-[5-(3-Hydroxy-2-phenylpropanoyl)-6,6-dimethyl-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazol-3-yl]-1-(trimethylsilyl)cyclobutanecarboxamide (Compound No. IV-1215)

To a solution of 1.10 g (2.02 mmol) of (R)—N-{5-[3-(benzyloxy)-2-phenylpropanoyl]-6,6-dimethyl-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazol-3-yl}-1-(trimethylsilyl)cyclobutanecarboxamide synthesized in the similar manner as in Example 86 in 15 ml of ethanol, 326 mg of 20% palladium hydroxide/carbon [containing 50 wt % water] was added at room temperature in a nitrogen atmosphere and then, after replacement with a hydrogen atmosphere under reduced pressure, stirred at room temperature for 3.5 hours.

After the completion of the reaction, the inside of the reaction container was replaced with a nitrogen atmosphere under reduced pressure. The reaction solution was filtered using a celite filter, subsequently the removed solid was washed with ethyl acetate, and then, the filtrate was concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=70:30 to 10:90 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was subjected again to silica gel column chromatography (elution solvent: dichloromethane:methanol=100:0 to 96:4 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was dissolved in ethyl acetate, then n-hexane was added, and the deposited solid was collected by filtration, washed with n-hexane, and then dried under reduced pressure to obtain 708 mg of the title compound (yield: 77%) as a white solid.

Mass spectrum (CI, m/z): 455 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.25 & 11.82 (s, total 1H), 9.66-9.47 (m, 1H), 7.36-7.20 (m, 5H), 4.83-4.62 (m, 2H), 4.32-4.13 (m, 1H), 3.99-3.90 (m, 1H), 3.89-3.79 (m, 1H), 3.53-3.42 (m, 1H), 2.57-2.35 (m, 2H), 2.25-2.09 (m, 2H), 1.91-1.64 (m, 5H), 1.63-1.52 (m, 3H), 0.13-0.01 (m, 9H).

(R)—N-[5-(2-Methoxy-2-phenylacetyl)-6,6-dimethyl-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazol-3-yl]-1-(trimethylsilyl)cyclobutanecarboxamide (Compound No. IV-1175)

To a solution of 263 mg (1.58 mmol) of (R)-2-methoxy-2-phenylacetic acid in 5 ml of dehydrated dichloromethane, 0.24 ml (2.8 mmol) of oxalyl chloride and 0.025 ml (0.32 mmol) of DMF were added in this order at 0° C. in an argon atmosphere and then stirred for 3 hours with the temperature unchanged.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure at room temperature to obtain a concentration residue.

To a solution of 300 mg (0.793 mmol) of ethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 84 and 0.55 ml (3.2 mmol) of DIPEA in 5 ml of dehydrated dichloromethane, a solution of the obtained concentration residue in 3 ml of dehydrated dichloromethane was added dropwise at 0° C. in an argon atmosphere and then stirred at room temperature for 15 hours. Subsequently, 0.37 ml (4.0 mmol) of N,N-dimethylethane-1,2-diamine was added to the reaction solution at room temperature and then stirred for 3 hours with the temperature unchanged.

After the completion of the reaction, a saturated aqueous solution of sodium bicarbonate was added to the reaction solution, followed by extraction with ethyl acetate. All of the obtained organic layers were washed with a saturated aqueous solution of ammonium chloride and a saturated aqueous solution of sodium chloride in this order, dried over anhydrous magnesium sulfate, then filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=50:50 to 35:65 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was dissolved by adding ethyl acetate, then n-hexane was added, and the deposited solid was collected by filtration and dried under reduced pressure to obtain 224 mg of the title compound (yield: 62%) as a white solid.

Mass spectrum (CI, m/z): 455 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.26 & 11.86 (br s, total 1H), 9.71-9.47 (m, 1H), 7.44-7.27 (m, 5H), 4.96 (s, 1H), 4.74-4.52 (m, 1H), 4.39-4.21 (m, 1H), 3.31 (s, 3H), 2.48-2.36 (m, 2H), 2.26-2.07 (m, 2H), 1.92-1.53 (m, 8H), 0.05 (s, 9H).

(S)—N-[5-(2-Methoxy-2-phenylacetyl)-6,6-dimethyl-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazol-3-yl]-1-(trimethylsilyl)cyclobutanecarboxamide (Compound No. IV-1176)

To a solution of 263 mg (1.58 mmol) of (S)-2-methoxy-2-phenylacetic acid in 5 ml of dehydrated dichloromethane, 0.24 ml (2.8 mmol) of oxalyl chloride and 0.025 ml (0.32 mmol) of DMF were added in this order at 0° C. in an argon atmosphere and then stirred for 3 hours with the temperature unchanged.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure at room temperature to obtain a concentration residue.

To a solution of 300 mg (0.793 mmol) of ethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 84 and 0.55 ml (3.2 mmol) of DIPEA in 5 ml of dehydrated dichloromethane, a solution of the obtained concentration residue in 3 ml of dehydrated dichloromethane was added dropwise at 0° C. in an argon atmosphere and then stirred at room temperature for 15 hours. Subsequently, 0.37 ml (4.0 mmol) of N,N-dimethylethane-1,2-diamine was added to the reaction solution at room temperature and then stirred for 3 hours with the temperature unchanged.

After the completion of the reaction, a saturated aqueous solution of sodium bicarbonate was added to the reaction solution, followed by extraction with ethyl acetate. All of the obtained organic layers were washed with a saturated aqueous solution of ammonium chloride and a saturated aqueous solution of sodium chloride in this order, dried over anhydrous magnesium sulfate, then filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=50:50 to 35:65 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was dissolved by adding ethyl acetate, then n-hexane was added, and the deposited solid was collected by filtration and dried under reduced pressure to obtain 206 mg of the title compound (yield: 57%) as a white solid.

Mass spectrum (CI, m/z): 455 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.26 & 11.86 (br s, total 1H), 9.71-9.45 (m, 1H), 7.46-7.26 (m, 5H), 4.96 (s, 1H), 4.73-4.53 (m, 1H), 4.30 (br d, J=12.3 Hz, 1H), 3.31 (s, 3H), 2.47-2.36 (m, 2H), 2.24-2.11 (m, 2H), 1.89-1.53 (m, 8H), 0.05 (s, 9H).

N-[5-(3-Methoxy-2-phenylpropanoyl)-6,6-dimethyl-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazol-3-yl]-1-(trimethylsilyl)cyclobutanecarboxamide (Compound No. IV-634)

To a solution of 212 mg (1.18 mmol) of 3-methoxy-2-phenylpropanoic acid synthesized in the similar manner as in Reference Example 72 in 6 ml of dehydrated dichloromethane, 0.14 ml (1.6 mmol) of oxalyl chloride and 0.0060 ml (0.077 mmol) of dehydrated DMF were added in this order at 0° C. in a nitrogen atmosphere and then stirred for 2.5 hours with the temperature unchanged.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure to obtain a concentration residue.

To a solution of 156 mg (0.413 mmol) of ethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 84 and 0.36 ml (2.1 mmol) of DIPEA in 3 ml of dehydrated dichloromethane, a solution of the obtained concentration residue in 1 ml of dehydrated dichloromethane was added at 0° C. in a nitrogen atmosphere and then stirred for 1.5 hours with the temperature unchanged. Subsequently, 0.23 ml (2.1 mmol) of N,N-dimethylethane-1,2-diamine was added to the reaction solution at 0° C. and then stirred at room temperature for 2 hours.

After the completion of the reaction, the reaction solution diluted with dichloromethane was washed with a 5% aqueous potassium bisulfate solution, and then the aqueous layer and the organic layer were separated. The aqueous layer was subjected to extraction with dichloromethane twice, and then, all of the obtained organic layers were dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=70:30 to 50:50 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was subjected again to silica gel column chromatography (elution solvent: dichloromethane:methanol=100:0 to 95:5 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was subjected to preparative HPLC (column: X-Bridge (trade name) ODS, elution solvent: acetonitrile:1 mM aqueous dipotassium hydrogen phosphate solution=40:60 (V/V)), a fraction containing the compound of interest was concentrated under reduced pressure, and acetonitrile was distilled off. The obtained concentration residue was subjected to extraction with ethyl acetate three times, and then, all of the obtained organic layers were washed with a saturated aqueous solution of sodium chloride, subsequently dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was dissolved in ethyl acetate, then n-hexane was added, and the deposited solid was collected by filtration, washed with n-hexane, and then dried under reduced pressure to obtain 101 mg of the title compound (yield: 52%) as a white solid.

Mass spectrum (CI, m/z): 469 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.50-11.61 (m, 1H), 9.57 (br s, 1H), 7.36-7.22 (m, 5H), 4.70 (d, J=12.3 Hz, 1H), 4.22 (d, J=12.3 Hz, 1H), 3.99-3.92 (m, 1H), 3.90-3.83 (m, 1H), 3.40 (dd, J=5.7, 8.8 Hz, 1H), 3.23 (s, 3H), 2.57-2.37 (m, 2H), 2.22-2.12 (m, 2H), 1.86-1.74 (m, 2H), 1.68 (s, 3H), 1.57 (s, 3H), 0.05 (s, 9H).

N-[5-(4-Methoxy-2-phenylbutanoyl)-6,6-dimethyl-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazol-3-yl]-1-(trimethylsilyl)cyclobutanecarboxamide (Compound No. IV-1224)

To a solution of 154 mg (0.793 mmol) of 4-methoxy-2-phenylbutanoic acid synthesized in the similar manner as in Reference Example 74 in 3 ml of dehydrated dichloromethane, 0.14 ml (1.6 mmol) of oxalyl chloride and 0.0092 ml (0.12 mmol) of DMF were added in this order at 0° C. in an argon atmosphere and then stirred for 1 hour with the temperature unchanged.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure at room temperature to obtain a concentration residue.

To a solution of 150 mg (0.396 mmol) of ethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 84 and 0.28 ml (1.6 mmol) of DIPEA in 3 ml of dehydrated dichloromethane, a solution of the obtained concentration residue in 3 ml of dehydrated dichloromethane was added dropwise at 0° C. in an argon atmosphere and then stirred at room temperature for 3 hours. Subsequently, 0.185 ml (1.98 mmol) of N,N-dimethylethane-1,2-diamine was added to the reaction solution at room temperature and then stirred for 14 hours with the temperature unchanged.

After the completion of the reaction, a saturated aqueous solution of sodium bicarbonate was added to the reaction solution, followed by extraction with ethyl acetate. All of the obtained organic layers were washed with a saturated aqueous solution of ammonium chloride and a saturated aqueous solution of sodium chloride in this order, dried over anhydrous magnesium sulfate, then filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=60:40 to 40:60 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was subjected to preparative HPLC (column: XSelect (trade name) HSS C18, elution solvent: acetonitrile:1 mM aqueous potassium dihydrogen phosphate solution=50:50 (V/V)), a fraction containing the compound of interest was concentrated under reduced pressure, and acetonitrile was distilled off. The obtained concentration residue was subjected to extraction with ethyl acetate, and all of the obtained organic layers were washed with a saturated aqueous solution of sodium chloride, dried over anhydrous magnesium sulfate, then filtered, and concentrated under reduced pressure. The obtained concentration residue was dissolved by adding ethyl acetate, then n-hexane was added, and the deposited solid was collected by filtration and dried under reduced pressure to obtain 78 mg of the title compound (yield: 41%) as a white solid.

Mass spectrum (CI, m/z): 483 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.24 & 11.95 (br s, total 1H), 9.78-9.46 (m, 1H), 7.39-7.18 (m, 5H), 4.79-4.57 (m, 1H), 4.24 (br d, J=12.2 Hz, 1H), 3.92-3.75 (m, 1H), 3.29-3.21 (m, 2H), 3.20 (s, 3H), 2.59-2.37 (m, 2H), 2.25-2.11 (m, 3H), 1.88-1.62 (m, 6H), 1.57 (br s, 3H), 0.05 (s, 9H).

(S)—N-[5-(3-Hydroxy-2-phenylpropanoyl)-6,6-dimethyl-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazol-3-yl]-1-(trimethylsilyl)cyclopropanecarboxamide (Compound No. III-592)

To a solution of 45.8 mg (0.0864 mmol) of (S)—N-{5-[3-(benzyloxy)-2-phenylpropanoyl]-6,6-dimethyl-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazol-3-yl}-1-(trimethylsilyl)cyclopropanecarboxamide synthesized in the similar manner as in Reference Example 75 in 1 ml of ethanol, 13.6 mg of 20% palladium hydroxide/carbon [containing 50 wt % water] was added at room temperature in a nitrogen atmosphere and then, after replacement with a hydrogen atmosphere under reduced pressure, stirred at room temperature for 2.5 hours.

After the completion of the reaction, the inside of the reaction container was replaced with a nitrogen atmosphere under reduced pressure. The reaction solution was filtered using a celite filter, subsequently the removed solid was washed with ethyl acetate, and then, the filtrate was concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=70:30 to 30:70 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was subjected again to silica gel column chromatography (elution solvent: dichloromethane:methanol=99:1 to 95:5 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was dissolved in ethyl acetate, then n-hexane was added, and the deposited solid was collected by filtration, washed with n-hexane, and then dried under reduced pressure to obtain 19 mg of the title compound (yield: 50%) as a white solid.

Mass spectrum (CI, m/z): 441 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.25 & 11.96 (br s, total 1H), 9.98-9.65 (m, 1H), 7.37-7.19 (m, 5H), 4.80-4.58 (m, 2H), 4.33-4.10 (m, 1H), 3.98-3.88 (m, 1H), 3.88-3.80 (m, 1H), 3.52-3.43 (m, 1H), 1.68 (br s, 3H), 1.57 (br s, 3H), 1.05-0.91 (m, 2H), 0.80-0.56 (m, 2H), 0.01 (s, 9H).

(R)—N-[5-(2-Methoxy-2-phenylacetyl)-6,6-dimethyl-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazol-3-yl]-1-(trimethylsilyl)cyclopropanecarboxamide (Compound No. III-1059)

To a solution of 182 mg (1.10 mmol) of (R)-2-methoxy-2-phenylacetic acid in 5 ml of dehydrated dichloromethane, 0.165 ml (1.92 mmol) of oxalyl chloride and 0.017 ml (0.22 mmol) of DMF were added in this order at 0° C. in an argon atmosphere and then stirred for 1 hour with the temperature unchanged.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure at room temperature to obtain a concentration residue.

To a solution of 200 mg (0.549 mmol) of ethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclopropanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 46 and 0.38 ml (2.2 mmol) of DIPEA in 5 ml of dehydrated dichloromethane, a solution of the obtained concentration residue in 3 ml of dehydrated dichloromethane was added dropwise at 0° C. in an argon atmosphere and then stirred at room temperature for 1.5 hours. Subsequently, 0.26 ml (2.7 mmol) of N,N-dimethylethane-1,2-diamine was added to the reaction solution at room temperature and then stirred for 1 hour with the temperature unchanged.

After the completion of the reaction, a saturated aqueous solution of sodium bicarbonate was added to the reaction solution, followed by extraction with ethyl acetate. All of the obtained organic layers were washed with a saturated aqueous solution of ammonium chloride and a saturated aqueous solution of sodium chloride in this order, dried over anhydrous magnesium sulfate, then filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=70:30 to 50:50 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was subjected again to silica gel column chromatography (elution solvent: 1,2-dichloroethane:methanol=97:3 to 90:10 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure and dried under reduced pressure to obtain 191 mg of the title compound (yield: 79%) as a white solid.

Mass spectrum (CI, m/z): 441 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.38-11.88 (m, 1H), 9.97-9.65 (m, 1H), 7.45-7.27 (m, 5H), 4.96 (s, 1H), 4.71-4.49 (m, 1H), 4.29 (br d, J=12.8 Hz, 1H), 3.31 (s, 3H), 1.68 (br s, 3H), 1.59 (s, 3H), 1.05-0.91 (m, 2H), 0.78-0.58 (m, 2H), 0.01 (s, 9H).

(R)—N-{5-[2-(Difluoromethoxy)-2-phenylacetyl]-6,6-dimethyl-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazol-3-yl}-1-(trimethylsilyl)cyclobutanecarboxamide (Compound No. IV-1180)

To a solution of 1.01 g (4.17 mmol) of (R)-benzyl 2-hydroxy-2-phenylacetate and 158 mg (0.83 mmol) of copper(I) iodide in 15 ml of acetonitrile, a solution of 2.2 ml (17 mmol) of 2,2-difluoro-2-(fluorosulfonyl)acetic acid in 20 ml of acetonitrile was dividedly added (2 ml each) every 5 minutes at 60° C. in an argon atmosphere and stirred for 2 hours with the temperature unchanged.

After the completion of the reaction, the reaction solution allowed to cool to room temperature was concentrated under reduced pressure and diluted with ethyl acetate. The organic layer was washed with a saturated aqueous solution of sodium bicarbonate and a saturated aqueous solution of sodium chloride in this order, then dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (elution solvent: n-hexane:ethyl acetate=90:10 to 70:30 (V/V)), and subsequently, a fraction containing the compound of interest was concentrated under reduced pressure to obtain 0.67 g of a concentration residue as a colorless oil.

To a solution of 0.67 g of the obtained concentration residue in 20 ml of methanol, 70 mg of palladium/carbon (ASCA2 (trade name), manufactured by N.E. Chemcat Corp., containing 54% water) was added in an argon atmosphere and then, after replacement with a hydrogen atmosphere under reduced pressure, stirred at room temperature for 2 hours.

After the completion of the reaction, replacement with a nitrogen atmosphere was performed, the reaction solution was filtered through celite, the solid component was washed with methanol, and then, the filtrate was concentrated under reduced pressure to obtain 0.42 g of a concentration residue as a pale yellow solid.

To a solution of 115 mg of the obtained concentration residue in 3 ml of dehydrated dichloromethane, 0.072 ml (0.82 mmol) of oxalyl chloride and 0.010 ml (0.13 mmol) of dehydrated DMF were added in this order at room temperature in an argon atmosphere and then stirred for 15 minutes with the temperature unchanged.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure to obtain a concentration residue.

To a solution of 103 mg (0.273 mmol) of ethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 84 and 0.24 ml (1.4 mmol) of DIPEA in 3 ml of dehydrated dichloromethane, a solution of the obtained concentration residue in 1 ml of dehydrated dichloromethane was added at room temperature in an argon atmosphere and then stirred for 3.5 hours with the temperature unchanged. Subsequently, 0.15 ml (1.4 mmol) of N,N-dimethylethane-1,2-diamine was added to the reaction solution at room temperature and then stirred at room temperature for 1 hour.

After the completion of the reaction, a 5% aqueous potassium bisulfate solution was added, followed by extraction with ethyl acetate. The organic layer was washed with a saturated aqueous solution of sodium bicarbonate and a saturated aqueous solution of sodium chloride in this order, dried by adding anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=50:50 to 0:100 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was dissolved in ethyl acetate, and n-hexane was added. The deposited solid was collected by filtration and dried under reduced pressure to obtain 48.1 mg of the title compound (yield: 36%) as a white solid.

Mass spectrum (CI, m/z): 491 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.30 & 11.86 (br s, total 1H), 9.67-9.51 (m, 1H), 7.48-7.37 (m, 5H), 6.83 (t, J=76.0 Hz, 1H), 5.78 (s, 1H), 4.83-4.61 (m, 1H), 4.24-4.07 (m, 1H), 2.56-2.35 (m, 2H), 2.24-2.10 (m, 2H), 1.91-1.50 (m, 8H), 0.04 (s, 9H).

(R)—N-[5-(2-Ethoxy-2-phenylacetyl)-6,6-dimethyl-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazol-3-yl]-1-(trimethylsilyl)cyclobutanecarboxamide (Compound No. IV-1188)

To a solution of 128 mg (0.710 mmol) of (R)-2-ethoxy-2-phenylacetic acid obtained in the similar manner as in Reference Example 77 in 3 ml of dehydrated dichloromethane, 0.090 ml (1.0 mmol) of oxalyl chloride and 0.010 ml (0.13 mmol) of dehydrated DMF were added in this order at 0° C. in an argon atmosphere and then stirred for 1 hour with the temperature unchanged.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure to obtain a concentration residue.

To a solution of 112 mg (0.295 mmol) of ethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 84 and 0.30 ml (1.7 mmol) of DIPEA in 3 ml of dehydrated dichloromethane, a solution of the obtained concentration residue in 1 ml of dehydrated dichloromethane was added at 0° C. in an argon atmosphere and then stirred for 30 minutes with the temperature unchanged. Subsequently, 0.11 ml (1.01 mmol) of N,N-dimethylethane-1,2-diamine was added to the reaction solution at 0° C. and then stirred at room temperature for 1 hour.

After the completion of the reaction, water was added, followed by extraction with ethyl acetate. The organic layer was washed with a 5% aqueous potassium bisulfate solution and a saturated aqueous solution of sodium chloride in this order, dried by adding anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=50:50 to 0:100 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was dissolved in ethyl acetate, n-hexane was added, and the deposited solid was collected by filtration and dried under reduced pressure to obtain 69.7 mg of the title compound (yield: 50%) as a white solid.

Mass spectrum (CI, m/z): 469 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.26 & 11.85 (br s, total 1H), 9.67-9.48 (m, 1H), 7.43-7.27 (m, 5H), 5.04 (s, 1H), 4.73-4.47 (m, 1H), 4.44-4.24 (m, 1H), 3.62-3.40 (m, 2H), 2.58-2.36 (m, 2H), 2.25-2.10 (m, 2H), 1.90-1.53 (m, 8H), 1.14 (t, J=7.0 Hz, 3H), 0.05 (s, 9H).

(R)-1-(Ethyldimethylsilyl)-N-[5-(2-methoxy-2-phenylacetyl)-6,6-dimethyl-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazol-3-yl]cyclobutanecarboxamide (Compound No. IV-1178)

To a solution of 107 mg (0.646 mmol) of (R)-2-methoxy-2-phenylacetic acid in 2 ml of dehydrated dichloromethane, 0.080 ml (0.93 mmol) of oxalyl chloride and 0.0050 ml (0.065 mmol) of dehydrated DMF were added in this order at 0° C. in a nitrogen atmosphere and then stirred for 3 hours with the temperature unchanged.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure to obtain a concentration residue.

To a solution of 117 mg (0.299 mmol) of ethyl 3-[1-(ethyldimethylsilyl)cyclobutanecarboxamido]-6,6-dimethyl-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 12 and 0.21 ml (1.2 mmol) of DIPEA in 1 ml of dehydrated dichloromethane, a solution of the obtained concentration residue in 1 ml of dehydrated dichloromethane was added at 0° C. in a nitrogen atmosphere and then stirred for 2.5 hours with the temperature unchanged. Subsequently, 0.16 ml (1.5 mmol) of N,N-dimethylethane-1,2-diamine was added to the reaction solution at 0° C. and then stirred at room temperature for 1.5 hours.

After the completion of the reaction, the reaction solution diluted with dichloromethane was washed with a 5% aqueous potassium bisulfate solution and then the aqueous layer and the organic layer were separated. The aqueous layer was subjected to extraction with dichloromethane twice, and then, all of the obtained organic layers were dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=80:20 to 50:50 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was dissolved in ethyl acetate, then n-hexane was added, and the deposited solid was collected by filtration, washed with n-hexane, and then dried under reduced pressure to obtain 115 mg of the title compound (yield: 82%) as a white solid.

Mass spectrum (CI, m/z): 469 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.26 & 11.84 (s, total 1H), 9.67-9.48 (m, 1H), 7.42-7.27 (m, 5H), 4.95 (s, 1H), 4.71-4.52 (m, 1H), 4.35-4.23 (m, 1H), 3.30 (s, 3H), 2.56-2.37 (m, 2H), 2.26-2.11 (m, 2H), 1.90-1.52 (m, 8H), 0.88 (t, J=7.8 Hz, 3H), 0.53 (q, J=7.8 Hz, 2H), 0.09-0.01 (m, 6H).

(R)—N-[5-(2-Cyclopropoxy-2-phenylacetyl)-6,6-dimethyl-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazol-3-yl]-1-(trimethylsilyl)cyclobutanecarboxamide (Compound No. IV-1208)

To a solution of 140 mg (0.728 mmol) of (R)-2-cyclopropoxy-2-phenylacetic acid synthesized in the similar manner as in Reference Example 86 in 2 ml of dehydrated dichloromethane, 0.006 ml (0.08 mmol) of DMF and 0.083 ml (0.95 mmol) of oxalyl chloride were added with stirring at 0° C. in an argon atmosphere and stirred at room temperature for 1.5 hours.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure to obtain a concentration residue.

To a solution of 150 mg (0.396 mmol) of ethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydro pyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 84 and 0.350 ml (2.00 mmol) of DIPEA in 2 ml of dehydrated dichloromethane, a solution of the obtained concentration residue in 3 ml of dehydrated dichloromethane was added dropwise with stirring at 0° C. in an argon atmosphere and stirred at room temperature for 2 hours.

After the completion of the reaction, a saturated aqueous solution of sodium bicarbonate was added to the reaction solution, followed by extraction with dichloromethane. The obtained organic layer was washed with water, then dried over anhydrous sodium sulfate, and filtered, and the filtrate was concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=100:0 to 70:30 (V/V)), subsequently concentrated under reduced pressure, and dried under reduced pressure to obtain a concentration residue.

To a solution of the obtained concentration residue in 2 ml of dehydrated dichloromethane, 0.130 ml (1.19 mmol) of N,N-dimethylethane-1,2-diamine was added at room temperature in an argon atmosphere and then stirred at room temperature for 16 hours.

After the completion of the reaction, a 5% aqueous potassium bisulfate solution was added to the reaction solution and stirred, followed by extraction with dichloromethane. The obtained organic layer was washed with a saturated aqueous solution of sodium bicarbonate and a saturated aqueous solution of sodium chloride in this order, then dried over anhydrous sodium sulfate, and filtered, and the filtrate was concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=100:0 to 50:50 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was dissolved in ethyl acetate and then added to n-hexane, and the deposited solid was collected by filtration and dried under reduced pressure to obtain 80 mg of the title compound (yield: 42%) as a white solid.

Mass spectrum (CI, m/z): 481 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.37-11.83 (m, 1H), 9.59 (br s, 1H), 7.42-7.28 (m, 5H), 5.10 (s, 1H), 4.73-4.54 (m, 1H), 4.35 (d, J=12.4 Hz, 1H), 3.40 (tt, J=3.0, 6.1 Hz, 1H), 2.59-2.37 (m, 2H), 2.24-2.12 (m, 2H), 1.90-1.74 (m, 2H), 1.70 (s, 3H), 1.61 (s, 3H), 0.69-0.53 (m, 2H), 0.51-0.39 (m, 2H), 0.05 (s, 9H).

(R)—N-[5-(2-Isopropoxy-2-phenylacetyl)-6,6-dimethyl-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazol-3-yl]-1-(trimethylsilyl)cyclobutanecarboxamide (Compound No. IV-1204)

To a solution of 165 mg (0.849 mmol) of (R)-2-isopropoxy-2-phenylacetic acid synthesized in the similar manner as in Reference Example 87 in 2 ml of dehydrated dichloromethane, 0.10 ml (1.2 mmol) of oxalyl chloride and 0.0050 ml (0.065 mmol) of dehydrated DMF were added in this order at 0° C. in an argon atmosphere and then stirred for 2.5 hours with the temperature unchanged.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure and dried under reduced pressure to obtain a concentration residue.

To a solution of 128 mg (0.338 mmol) of ethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 84 and 0.30 ml (1.7 mmol) of DIPEA in 1 ml of dehydrated dichloromethane, a solution of the obtained concentration residue in 1 ml of dehydrated dichloromethane was added at 0° C. in an argon atmosphere and then stirred for 1.5 hours with the temperature unchanged.

After the completion of the reaction, ethyl acetate and a saturated aqueous solution of sodium bicarbonate were added to the reaction solution and stirred. After separation into an aqueous layer and an organic layer, the aqueous layer was subjected to extraction with ethyl acetate twice. All of the organic layers were dried over anhydrous magnesium sulfate, then filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (elution solvent: n-hexane:ethyl acetate=80:20 to 60:40 (V/V)), subsequently concentrated under reduced pressure, and dried under reduced pressure to obtain a concentration residue.

To a solution of the obtained concentration residue in 2 ml of THF, 0.15 ml (1.4 mmol) of N,N-dimethylethane-1,2-diamine was added at room temperature in an argon atmosphere and then stirred at room temperature for 2 hours.

After the completion of the reaction, a 5% aqueous potassium bisulfate solution was added to the reaction solution and stirred, followed by extraction with ethyl acetate three times. All of the obtained organic layers were dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=80:20 to 50:50 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was dissolved in ethyl acetate, then n-hexane was added, and the deposited solid was collected by filtration, washed with n-hexane, and then dried under reduced pressure to obtain 135 mg of the title compound (yield: 83%) as a white solid.

Mass spectrum (CI, m/z): 483 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.40-11.82 (m, 1H), 9.75-9.42 (m, 1H), 7.40-7.27 (m, 5H), 5.11 (s, 1H), 4.65-4.38 (m, 2H), 3.68 (spt, J=6.0 Hz, 1H), 2.47-2.35 (m, 2H), 2.23-2.09 (m, 2H), 1.87-1.71 (m, 2H), 1.67 (s, 3H), 1.61 (s, 3H), 1.16 (d, J=6.0 Hz, 3H), 1.13 (d, J=6.0 Hz, 3H), 0.04 (s, 9H).

(R)—N-{6,6-Dimethyl-5-[2-phenyl-2-(trifluoromethoxy)acetyl]-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazol-3-yl}-1-(trimethylsilyl)cyclobutanecarboxamide (Compound No. IV-1184)

To a solution of 160 mg of (R)-2-phenyl-2-(trifluoromethoxy)acetic acid (containing impurities) synthesized in the similar manner as in Reference Example 89 in 2 ml of dehydrated dichloromethane, 0.083 ml (0.95 mmol) of oxalyl chloride and 0.006 ml (0.08 mmol) of DMF were added with stirring at 0° C. in an argon atmosphere and stirred at room temperature for 1.5 hours.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure to obtain a concentration residue.

To a solution of 150 mg (0.396 mmol) of ethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 84 and 0.350 ml (2.00 mmol) of DIPEA in 2 ml of dehydrated dichloromethane, a solution of the obtained concentration residue in 3 ml of dehydrated dichloromethane was added dropwise with stirring at 0° C. in an argon atmosphere and stirred at room temperature for 2 hours.

After the completion of the reaction, a saturated aqueous solution of sodium bicarbonate was added to the reaction solution, followed by extraction with dichloromethane. The obtained organic layer was washed with water, then dried over anhydrous sodium sulfate, and filtered, and the filtrate was concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=100:0 to 70:30 (V/V)), subsequently concentrated under reduced pressure, and dried under reduced pressure to obtain a concentration residue.

To a solution of the obtained concentration residue in 2 ml of dehydrated dichloromethane, 0.130 ml (1.19 mmol) of N,N-dimethylethane-1,2-diamine was added at room temperature in an argon atmosphere and then stirred at room temperature for 2 hours.

After the completion of the reaction, a 5% aqueous potassium bisulfate solution was added to the reaction solution and stirred, followed by extraction with dichloromethane. The obtained organic layer was washed with a saturated aqueous solution of sodium bicarbonate and a saturated aqueous solution of sodium chloride in this order, then dried over anhydrous sodium sulfate, and filtered, and the filtrate was concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=100:0 to 50:50 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was dissolved in ethyl acetate and then added to n-hexane, and the deposited solid was collected by filtration and dried under reduced pressure to obtain 97.6 mg of the title compound (yield: 48%) as a white solid.

Mass spectrum (CI, m/z): 509 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.39-11.84 (m, 1H), 9.58 (br s, 1H), 7.54-7.41 (m, 5H), 6.06 (s, 1H), 4.78 (br d, J=11.9 Hz, 1H), 4.08 (br d, J=11.9 Hz, 1H), 2.58-2.35 (m, 2H), 2.23-2.10 (m, 2H), 1.88-1.73 (m, 2H), 1.70 (s, 3H), 1.60 (s, 3H), 0.04 (s, 9H).

(R)—N-[6,6-Dimethyl-5-(2-phenyl-2-propoxyacetyl)-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazol-3-yl]-1-(trimethylsilyl)cyclobutanecarboxamide (Compound No. IV-1196)

To a solution of 146 mg (0.753 mmol) of (R)-2-phenyl-2-propoxyacetic acid synthesized in the similar manner as in Reference Example 91 in 2 ml of dehydrated dichloromethane, 0.10 ml (1.2 mmol) of oxalyl chloride and 0.0050 ml (0.065 mmol) of dehydrated DMF were added in this order at 0° C. in an argon atmosphere and then stirred for 1.5 hours with the temperature unchanged.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure and dried under reduced pressure to obtain a concentration residue.

To a solution of 144 mg (0.380 mmol) of ethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 84 and 0.33 ml (1.9 mmol) of DIPEA in 1 ml of dehydrated dichloromethane, a solution of the obtained concentration residue in 1 ml of dehydrated dichloromethane was added at 0° C. in an argon atmosphere and then stirred for 1.5 hours with the temperature unchanged.

After the completion of the reaction, ethyl acetate and a saturated aqueous solution of sodium bicarbonate were added to the reaction solution and stirred. After separation into an aqueous layer and an organic layer, the aqueous layer was subjected to extraction with ethyl acetate twice. All of the organic layers were dried over anhydrous magnesium sulfate, then filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (elution solvent: n-hexane:ethyl acetate=85:15 to 60:40 (V/V)), subsequently concentrated under reduced pressure, and dried under reduced pressure to obtain a concentration residue.

To a solution of the obtained concentration residue in 2 ml of THF, 0.17 ml (1.6 mmol) of N,N-dimethylethane-1,2-diamine was added at room temperature in an argon atmosphere and then stirred at room temperature for 3 hours.

After the completion of the reaction, a 5% aqueous potassium bisulfate solution was added to the reaction solution and stirred, followed by extraction with ethyl acetate three times. All of the obtained organic layers were dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=85:15 to 60:40 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was dissolved in ethyl acetate, then n-hexane was added, and the deposited solid was collected by filtration, washed with n-hexane, and then dried under reduced pressure to obtain 144 mg of the title compound (yield: 80%) as a white solid.

Mass spectrum (CI, m/z): 483 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.43-11.75 (m, 1H), 9.56 (br s, 1H), 7.43-7.27 (m, 5H), 5.03 (s, 1H), 4.71-4.47 (m, 1H), 4.39 (br d, J=12.5 Hz, 1H), 3.51-3.43 (m, 1H), 3.41-3.24 (m, 1H), 2.60-2.36 (m, 2H), 2.25-2.10 (m, 2H), 1.88-1.72 (m, 2H), 1.68 (s, 3H), 1.65-1.48 (m, 5H), 0.87 (t, J=7.4 Hz, 3H), 0.04 (s, 9H).

N-{5-[2-(4-Fluorophenyl)-2-methoxyacetyl]-6,6-dimethyl-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazol-3-yl}-1-(trimethylsilyl)cyclobutanecarboxamide (Compound No. IV-1427)

To a suspension of 229 mg of 2-(4-fluorophenyl)-2-methoxyacetic acid (containing impurities) synthesized in the similar manner as in Reference Example 93 in 2 ml of dehydrated dichloromethane, 0.150 ml (1.71 mmol) of oxalyl chloride and 0.011 ml (0.14 mmol) of DMF were added with stirring at 0° C. in an argon atmosphere and stirred at room temperature for 1.5 hours.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure to obtain a concentration residue.

To a solution of 265 mg (0.700 mmol) of ethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 84 and 0.620 ml (3.55 mmol) of DIPEA in 2 ml of dehydrated dichloromethane, a solution of the obtained concentration residue in 3 ml of dehydrated dichloromethane was added dropwise with stirring at 0° C. in an argon atmosphere and stirred at room temperature for 1 hour.

After the completion of the reaction, a saturated aqueous solution of sodium bicarbonate was added to the reaction solution, followed by extraction with dichloromethane. The obtained organic layer was washed with water, then dried over anhydrous sodium sulfate, and filtered, and the filtrate was concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=100:0 to 70:30 (V/V)), subsequently concentrated under reduced pressure, and dried under reduced pressure to obtain a concentration residue.

To a solution of the obtained concentration residue in 2 ml of dehydrated dichloromethane, 0.230 ml (2.11 mmol) of N,N-dimethylethane-1,2-diamine was added at room temperature in an argon atmosphere and then stirred at room temperature for 1 hour.

After the completion of the reaction, a 5% aqueous potassium bisulfate solution was added to the reaction solution and stirred, followed by extraction with dichloromethane. The obtained organic layer was washed with a saturated aqueous solution of sodium bicarbonate and a saturated aqueous solution of sodium chloride in this order, then dried over anhydrous sodium sulfate, and filtered, and the filtrate was concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=100:0 to 50:50 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was dissolved in dichloromethane, and then, a 5% aqueous potassium bisulfate solution was added thereto, stirred, and separated into an aqueous layer and an organic layer. The obtained organic layer was washed with a saturated aqueous solution of sodium bicarbonate and a saturated aqueous solution of sodium chloride in this order, then dried over anhydrous sodium sulfate, and filtered, and the filtrate was concentrated under reduced pressure. The obtained concentration residue was dissolved in ethyl acetate and then added to n-hexane, and the deposited solid was collected by filtration and dried under reduced pressure to obtain 174 mg of the title compound (yield: 53%) as a white solid.

Mass spectrum (CI, m/z): 473 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.27 & 11.91 (br s, total 1H), 9.58 (br s, 1H), 7.47-7.36 (m, 2H), 7.26-7.14 (m, 2H), 4.99 (s, 1H), 4.76-4.53 (m, 1H), 4.32 (br d, J=12.4 Hz, 1H), 3.29 (s, 3H), 2.58-2.36 (m, 2H), 2.25-2.10 (m, 2H), 1.88-1.72 (m, 2H), 1.69 (br s, 3H), 1.60 (s, 3H), 0.05 (s, 9H).

N-{5-[2-(3-Fluorophenyl)-2-methoxyacetyl]-6,6-dimethyl-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazol-3-yl}-1-(trimethylsilyl)cyclobutanecarboxamide (Compound No. IV-1404)

To a suspension of 146 mg of 2-(3-fluorophenyl)-2-methoxyacetic acid (containing impurities) synthesized in the similar manner as in Reference Example 96 in 2 ml of dehydrated dichloromethane, 0.080 ml (0.91 mmol) of oxalyl chloride and 0.010 ml (0.13 mmol) of DMF were added with stirring at 0° C. in an argon atmosphere and stirred at room temperature for 1.5 hours.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure to obtain a concentration residue.

To a solution of 200 mg (0.528 mmol) of ethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 84 and 0.462 ml (2.65 mmol) of DIPEA in 2 ml of dehydrated dichloromethane, a solution of the obtained concentration residue in 3 ml of dehydrated dichloromethane was added dropwise with stirring at room temperature in an argon atmosphere and stirred at room temperature for 1 hour.

After the completion of the reaction, a saturated aqueous solution of sodium bicarbonate was added to the reaction solution, followed by extraction with dichloromethane. The obtained organic layer was washed with water, then dried over anhydrous sodium sulfate, and filtered, and the filtrate was concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=100:0 to 70:30 (V/V)), subsequently concentrated under reduced pressure, and dried under reduced pressure to obtain a concentration residue.

To a solution of the obtained concentration residue in 2 ml of dehydrated dichloromethane, 0.173 ml (1.59 mmol) of N,N-dimethylethane-1,2-diamine was added at room temperature in an argon atmosphere and then stirred at room temperature for 16 hours.

After the completion of the reaction, a 5% aqueous potassium bisulfate solution was added to the reaction solution and stirred, followed by extraction with dichloromethane. The obtained organic layer was washed with a saturated aqueous solution of sodium bicarbonate and a saturated aqueous solution of sodium chloride in this order, then dried over anhydrous sodium sulfate, and filtered, and the filtrate was concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=100:0 to 50:50 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was dissolved in methanol and then added to water, and the deposited solid was collected by filtration and dried under reduced pressure to obtain 187 mg of the title compound (yield: 75%) as a white solid.

Mass spectrum (CI, m/z): 473 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.40-11.81 (m, 1H), 9.60 (br s, 1H), 7.48-7.38 (m, 1H), 7.24-7.13 (m, 3H), 5.03 (s, 1H), 4.75-4.54 (m, 1H), 4.39 (br d, J=12.7 Hz, 1H), 3.32 (s, 3H), 2.59-2.36 (m, 2H), 2.24-2.10 (m, 2H), 1.88-1.72 (m, 2H), 1.69 (s, 3H), 1.60 (s, 3H), 0.05 (s, 9H).

(R)—N-{5-[2-(2-Fluorophenyl)-2-methoxyacetyl]-6,6-dimethyl-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazol-3-yl}-1-(trimethylsilyl)cyclobutanecarboxamide (Compound No. IV-1383)

To a suspension of 200 mg (1.09 mmol) of (R)-2-(2-fluorophenyl)-2-methoxyacetic acid synthesized in the similar manner as in Reference Example 98 in 2 ml of dehydrated dichloromethane, 0.111 ml (1.27 mmol) of oxalyl chloride and 0.010 ml (0.13 mmol) of DMF were added with stirring at 0° C. in an argon atmosphere and stirred at room temperature for 1.5 hours.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure to obtain a concentration residue.

To a solution of 200 mg (0.528 mmol) of ethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 84 and 0.500 ml (2.86 mmol) of DIPEA in 2 ml of dehydrated dichloromethane, a solution of the obtained concentration residue in 3 ml of dehydrated dichloromethane was added dropwise with stirring at room temperature in an argon atmosphere and stirred at room temperature for 2 hours.

After the completion of the reaction, a saturated aqueous solution of sodium bicarbonate was added to the reaction solution, followed by extraction with dichloromethane. The obtained organic layer was washed with water, then dried over anhydrous sodium sulfate, and filtered, and the filtrate was concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=100:0 to 70:30 (V/V)), subsequently concentrated under reduced pressure, and dried under reduced pressure to obtain a concentration residue.

To a solution of the obtained concentration residue in 2 ml of dehydrated dichloromethane, 0.173 ml (1.59 mmol) of N,N-dimethylethane-1,2-diamine was added at room temperature in an argon atmosphere and then stirred at room temperature for 3 hours.

After the completion of the reaction, a 5% aqueous potassium bisulfate solution was added to the reaction solution and stirred, followed by extraction with dichloromethane. The obtained organic layer was washed with a saturated aqueous solution of sodium bicarbonate and a saturated aqueous solution of sodium chloride in this order, then dried over anhydrous sodium sulfate, and filtered, and the filtrate was concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=100:0 to 50:50 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was dissolved in methanol and then added to water, and the deposited solid was collected by filtration and dried under reduced pressure to obtain 164 mg of the title compound (yield: 66%) as a white solid.

Mass spectrum (CI, m/z): 473 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.42-11.83 (m, 1H), 9.60 (br s, 1H), 7.46-7.34 (m, 2H), 7.27-7.18 (m, 2H), 5.22 (s, 1H), 4.75 (d, J=12.3 Hz, 1H), 4.20 (d, J=12.3 Hz, 1H), 3.32 (s, 3H), 2.58-2.37 (m, 2H), 2.25-2.11 (m, 2H), 1.88-1.73 (m, 2H), 1.70 (s, 3H), 1.60 (s, 3H), 0.05 (s, 9H).

N-{5-[2-Methoxy-2-(thiophen-2-yl)acetyl]-6,6-dimethyl-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazol-3-yl}-1-(trimethylsilyl)cyclobutanecarboxamide (Compound No. IV-1546)

To a suspension of 60 mg of 2-methoxy-2-(thiophen-2-yl)acetic acid (containing impurities) synthesized in the similar manner as in Reference Example 101 in 2 ml of dehydrated dichloromethane, 0.036 ml (0.41 mmol) of oxalyl chloride and 0.005 ml (0.07 mmol) of DMF were added with stirring at 0° C. in an argon atmosphere and stirred at room temperature for 1.5 hours.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure to obtain a concentration residue.

To a solution of 120 mg (0.317 mmol) of ethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 84 and 0.166 ml (0.950 mmol) of DIPEA in 2 ml of dehydrated dichloromethane, a solution of the obtained concentration residue in 3 ml of dehydrated dichloromethane was added dropwise with stirring at 0° C. in an argon atmosphere and stirred at room temperature for 2 hours.

After the completion of the reaction, a saturated aqueous solution of sodium bicarbonate was added to the reaction solution, followed by extraction with dichloromethane. The obtained organic layer was washed with water, then dried over anhydrous sodium sulfate, and filtered, and the filtrate was concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=100:0 to 70:30 (V/V)), subsequently concentrated under reduced pressure, and dried under reduced pressure to obtain a concentration residue.

To a solution of the obtained concentration residue in 2 ml of dehydrated dichloromethane, 0.104 ml (0.954 mmol) of N,N-dimethylethane-1,2-diamine was added at room temperature in an argon atmosphere and then stirred at room temperature for 16 hours.

After the completion of the reaction, a 5% aqueous potassium bisulfate solution was added to the reaction solution and stirred, followed by extraction with dichloromethane. The obtained organic layer was washed with a saturated aqueous solution of sodium bicarbonate and a saturated aqueous solution of sodium chloride in this order, then dried over anhydrous sodium sulfate, and filtered, and the filtrate was concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=100:0 to 50:50 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was dissolved in methanol and then added to water, and the deposited solid was collected by filtration and dried under reduced pressure to obtain 62 mg of the title compound (yield: 42%) as a white solid.

Mass spectrum (CI, m/z): 461 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.41-11.86 (m, 1H), 9.82-9.47 (m, 1H), 7.57 (dd, J=1.3, 5.0 Hz, 1H), 7.13-7.06 (m, 1H), 7.01 (dd, J=3.5, 5.0 Hz, 1H), 5.26 (s, 1H), 4.84-4.64 (m, 1H), 4.41 (br d, J=12.4 Hz, 1H), 3.28 (s, 3H), 2.58-2.37 (m, 2H), 2.26-2.10 (m, 2H), 1.89-1.73 (m, 2H), 1.70 (s, 3H), 1.62 (s, 3H), 0.06 (s, 9H).

(−)-N-{5-[2-Methoxy-2-(thiophen-2-yl)acetyl]-6,6-dimethyl-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazol-3-yl}-1-(trimethylsilyl)cyclobutanecarboxamide (Compound No. IV-1548)

0.041 g (0.089 mmol) of N-{5-[2-methoxy-2-(thiophen-2-yl)acetyl]-6,6-dimethyl-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazol-3-yl}-1-(trimethylsilyl)cyclobutanecarboxamide synthesized in the similar manner as in Example 104 was subjected to optical resolution preparative chromatography (column: CHIRALPAK (trade name) ID, elution solvent: n-hexane:ethanol=85:15 (V/V)), and a fraction containing an optically active form eluted first was concentrated under reduced pressure to obtain 17 mg of the title compound (yield: 41%) as a white solid.

Specific optical rotation: [α] D 20 =−51 (c=0.20, methanol).

Mass spectrum (CI, m/z): 461 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.23 (br s, 1H), 9.67 (br s, 1H), 7.57 (dd, J=1.2, 5.0 Hz, 1H), 7.13-7.06 (m, 1H), 7.01 (dd, J=3.5, 5.0 Hz, 1H), 5.26 (s, 1H), 4.74 (br d, J=12.5 Hz, 1H), 4.41 (d, J=12.5 Hz, 1H), 3.28 (s, 3H), 2.58-2.37 (m, 2H), 2.24-2.11 (m, 2H), 1.89-1.74 (m, 2H), 1.70 (s, 3H), 1.62 (s, 3H), 0.06 (s, 9H).

HPLC analysis:

Column: CHIRALPAK (trade name) ID 4.6×250 mm

Eluent: n-hexane/ethanol=85/15 (V/V)

Flow rate: 1.0 ml/min

Temperature: 40° C.

Detection wavelength: 254 nm

Retention time: 7.6 min.

Optical purity: >99% ee

(+)-N-{5-[2-Methoxy-2-(thiophen-2-yl)acetyl]-6,6-dimethyl-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazol-3-yl}-1-(trimethylsilyl)cyclobutanecarboxamide (Compound No. IV-1547)

A fraction containing an optically active form eluted later in the optical resolution preparative chromatography operation of Example 105 was concentrated under reduced pressure to obtain 14 mg of the title compound (yield: 34%) as a white solid.

Specific optical rotation: [α] D 20 =+66° (c=0.20, methanol).

Mass spectrum (CI, m/z): 461 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.23 (br s, 1H), 9.66 (br s, 1H), 7.57 (dd, J=1.2, 5.0 Hz, 1H), 7.14-7.06 (m, 1H), 7.01 (dd, J=3.5, 5.0 Hz, 1H), 5.26 (s, 1H), 4.74 (br d, J=12.4 Hz, 1H), 4.41 (d, J=12.4 Hz, 1H), 3.28 (s, 3H), 2.58-2.37 (m, 2H), 2.26-2.10 (m, 2H), 1.89-1.74 (m, 2H), 1.70 (s, 3H), 1.62 (s, 3H), 0.06 (s, 9H).

HPLC analysis:

Column: CHIRALPAK (trade name) ID 4.6×250 mm

Eluent: n-hexane/ethanol=85/15 (V/V)

Flow rate: 1.0 ml/min

Temperature: 40° C.

Detection wavelength: 254 nm

Retention time: 9.7 min.

Optical purity: >99% ee

N-{[1-(Hydroxymethyl)cyclobutyl](phenyl)methyl}-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. IV-718)

To a solution of a mixture of 131 mg (0.243 mmol) of 2-ethyl 5-(trichloromethyl) 6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]pyrrolo[3,4-c]pyrazole-2,5(4H,6H)-dicarboxylate synthesized in the similar manner as in Reference Example 102 and 79 mg (0.18 mmol) of ethyl 5-(chlorocarbonyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate in 3 ml of dehydrated 1,4-dioxane, 0.34 ml (2.0 mmol) of DIPEA and 235 mg (1.23 mmol) of {1-[amino(phenyl)methyl]cyclobutyl}methanol synthesized in the similar manner as in Reference Example 103 were added in this order at room temperature in an argon atmosphere and then stirred at 90° C. for 1.5 hours. After standing to cool until the reaction solution becomes room temperature, 0.21 ml (1.9 mmol) of N,N-dimethylethane-1,2-diamine was added at room temperature and stirred for 2 hours with the temperature unchanged.

After the completion of the reaction, a 5% aqueous potassium bisulfate solution was added to the reaction solution and stirred, followed by extraction with ethyl acetate three times. All of the organic layers were dried over anhydrous magnesium sulfate, then filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=60:40 to 30:70 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was dissolved in ethyl acetate, then n-hexane was added, and the deposited solid was collected by filtration, washed with n-hexane, and then dried under reduced pressure to obtain 187 mg of a white solid. The obtained solid was subjected to preparative HPLC (column: X-Bridge (trade name) ODS, elution solvent: acetonitrile:1 mM aqueous potassium dihydrogen phosphate solution=50:50 (V/V)), a fraction containing the compound of interest was concentrated under reduced pressure, and acetonitrile was distilled off. The solid deposited in the course of concentration was collected by filtration, washed with water, and then dried under reduced pressure to obtain 156 mg of the title compound (yield: 70%) as a white solid.

Mass spectrum (CI, m/z): 524 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.34-11.78 (m, 1H), 9.87-9.34 (m, 1H), 7.35-7.27 (m, 4H), 7.24-7.16 (m, 1H), 6.75 (d, J=7.9 Hz, 1H), 5.49 (br s, 1H), 4.95 (d, J=7.9 Hz, 1H), 4.47-4.20 (m, 2H), 3.49-3.41 (m, 1H), 3.26-3.18 (m, 1H), 2.57-2.39 (m, 2H), 2.26-2.14 (m, 2H), 2.11-1.99 (m, 2H), 1.98-1.74 (m, 5H), 1.61 (s, 3H), 1.53 (s, 3H), 1.26-1.13 (m, 1H), 0.08 (s, 9H).

(R)—N-[2-(1-Hydroxycyclopropyl)-1-phenylethyl]-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. IV-743)

To a solution of 128 mg of (R)-1-(2-amino-2-phenylethyl)cyclopropanol (containing impurities) synthesized in the similar manner as in Reference Example 105 in 2 ml of dehydrated 1,4-dioxane, 0.26 ml (1.5 mmol) of DIPEA and 154 mg (0.349 mmol) of ethyl 5-(chlorocarbonyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 3 were added in this order at room temperature in an argon atmosphere and then stirred at 90° C. for 2 hours. After standing to cool until the reaction solution becomes room temperature, 0.16 ml (1.5 mmol) of N,N-dimethylethane-1,2-diamine was added at room temperature and stirred for 2 hours with the temperature unchanged.

After the completion of the reaction, a 5% aqueous potassium bisulfate solution was added to the reaction solution and stirred, followed by extraction with ethyl acetate twice. All of the obtained organic layers were dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=70:30 to 40:60 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was suspended in an ethyl acetate/n-hexane mixed solvent and stirred, and then, insoluble matter was collected by filtration, washed with n-hexane, and then dried under reduced pressure to obtain 139 mg of the title compound (yield: 79%) as a white solid.

Mass spectrum (CI, m/z): 510 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.23 & 11.80 (br s, total 1H), 9.75-9.47 (m, 1H), 7.43-7.37 (m, 2H), 7.34-7.27 (m, 2H), 7.23-7.17 (m, 1H), 6.51-6.33 (m, 1H), 5.54-5.37 (m, 1H), 5.14-5.05 (m, 1H), 4.66-4.29 (m, 2H), 2.61-2.39 (m, 2H), 2.26-2.06 (m, 3H), 1.90-1.50 (m, 9H), 0.55-0.37 (m, 3H), 0.18-0.04 (m, 10H).

(R)—N-(3-Ethyl-3-Hydroxy-1-phenylpentyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. IV-759)

To a solution of 118 mg (0.568 mmol) of (R)-1-amino-3-ethyl-1-phenylpentan-3-ol synthesized in the similar manner as in Reference Example 107 in 2 ml of dehydrated 1,4-dioxane, 0.20 ml (1.1 mmol) of DIPEA and 128 mg (0.290 mmol) of ethyl 5-(chlorocarbonyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 3 were added in this order at room temperature in an argon atmosphere and then stirred at 90° C. for 2 hours.

After the completion of the reaction, a saturated aqueous solution of sodium bicarbonate was added to the reaction solution and stirred, followed by extraction with ethyl acetate three times. All of the organic layers were dried over anhydrous magnesium sulfate, then filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (elution solvent: n-hexane:ethyl acetate=75:25 to 40:60 (V/V)), subsequently concentrated under reduced pressure, and dried under reduced pressure to obtain a concentration residue.

To a solution of the obtained concentration residue in 2 ml of THF, 0.13 ml (1.2 mmol) of N,N-dimethylethane-1,2-diamine was added at room temperature in an argon atmosphere and then stirred at room temperature for 2 hours.

After the completion of the reaction, a 5% aqueous potassium bisulfate solution was added to the reaction solution and stirred, followed by extraction with ethyl acetate three times. All of the obtained organic layers were dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=70:30 to 30:70 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was suspended in an ethyl acetate/n-hexane mixed solvent and stirred at room temperature, and then, insoluble matter was collected by filtration, washed with n-hexane, and then dried under reduced pressure to obtain 123 mg of the title compound (yield: 79%) as a white solid.

Mass spectrum (CI, m/z): 540 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.35-11.68 (m, 1H), 9.56 (br s, 1H), 7.37-7.24 (m, 4H), 7.19-7.13 (m, 1H), 6.56 (d, J=5.8 Hz, 1H), 4.91-4.81 (m, 1H), 4.54-4.31 (m, 3H), 2.58-2.41 (m, 2H), 2.26-2.13 (m, 2H), 1.95-1.73 (m, 3H), 1.63-1.55 (m, 4H), 1.53 (s, 3H), 1.49-1.33 (m, 4H), 0.82 (t, J=7.4 Hz, 3H), 0.77 (t, J=7.4 Hz, 3H), 0.09 (s, 9H).

(R)—N-[1-(4-Fluorophenyl)-3-hydroxy-3-methylbutyl]-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. IV-939)

To a solution of 599 mg (1.36 mmol) of ethyl 5-(chlorocarbonyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 3 in 3 ml of 1,4-dioxane, 134 mg of (R)-4-amino-4-(4-fluorophenyl)-2-methylbutan-2-ol (containing impurities) synthesized in the similar manner as in Reference Example 111 and 0.602 ml (3.40 mmol) of DIPEA were added in this order at room temperature under argon stream and then stirred at 100° C. for 1 hour. Subsequently, 0.318 ml (3.40 mmol) of N,N-dimethylethane-1,2-diamine was added at room temperature and stirred for 2 hours with the temperature unchanged.

After the completion of the reaction, a 5% aqueous potassium bisulfate solution was added to the reaction solution, followed by extraction with ethyl acetate. The obtained organic layer was washed with a saturated aqueous solution of sodium chloride in this order, dried over anhydrous magnesium sulfate, then filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: ethyl acetate:methanol=100:0 to 90:10 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was subjected to preparative HPLC (column: X-Bridge (trade name) ODS, elution solvent: acetonitrile:1 mM aqueous potassium dihydrogen phosphate solution=30:70 to 50:50 (V/V)), a fraction containing the compound of interest was concentrated under reduced pressure, and acetonitrile was distilled off, followed by extraction with ethyl acetate. The obtained organic layer was washed with a saturated aqueous solution of sodium chloride, dried over anhydrous magnesium sulfate, then filtered, concentrated under reduced pressure, and dried under reduced pressure to obtain 48 mg of the title compound (yield: 8% [2 steps]) as a white solid.

Mass spectrum (CI, m/z): 530 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.20 & 11.77 (br s, total 1H), 9.74-9.41 (m, 1H), 7.40-7.32 (m, 2H), 7.14-7.05 (m, 2H), 6.66-6.44 (m, 1H), 4.94-4.84 (m, 1H), 4.75-4.60 (m, 1H), 4.52-4.31 (m, 2H), 2.59-2.39 (m, 2H), 2.27-2.11 (m, 2H), 2.04-1.73 (m, 3H), 1.70-1.45 (m, 7H), 1.15 (s, 3H), 1.13 (s, 3H), 0.09 (s, 9H).

(R)—N-[1-(3-Fluorophenyl)-3-hydroxy-3-methylbutyl]-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. IV-911)

To a solution of 149 mg (0.248 mmol) of (R)-ethyl 5-{[1-(3-fluorophenyl)-3-hydroxy-3-methylbutyl]carbamoyl}-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 116 in 3 ml of dichloromethane, 0.108 ml (0.992 mmol) of N,N-dimethylethane-1,2-diamine was added in one portion with stirring at room temperature under argon stream and stirred at room temperature for 1 hour.

After the completion of the reaction, a 5% aqueous potassium bisulfate solution was added to the reaction solution, followed by extraction from the mixed solution with ethyl acetate twice. The organic layer was washed with a 5% aqueous potassium bisulfate solution, dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=70:30 to 17:83 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was dissolved in a small amount of ethyl acetate, and a solid was deposited by adding n-hexane. The solid was collected by filtration, washed with n-hexane, and dried under reduced pressure at 50° C. to obtain 101 mg of the title compound (yield: 77%) as a white solid.

Mass spectrum (CI, m/z): 530 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.21 & 11.77 (br s, total 1H), 9.71-9.47 (m, 1H), 7.37-7.26 (m, 1H), 7.22-7.11 (m, 2H), 7.02-6.92 (m, 1H), 6.65-6.51 (m, 1H), 4.95-4.87 (m, 1H), 4.76-4.60 (m, 1H), 4.55-4.35 (m, 2H), 2.57-2.40 (m, 2H), 2.27-2.12 (m, 2H), 2.03-1.74 (m, 3H), 1.66 (dd, J=3.1, 14.2 Hz, 1H), 1.59 (br s, 3H), 1.54 (br s, 3H), 1.16 (s, 3H), 1.13 (s, 3H), 0.09 (s, 9H).

(R)—N-[1-(2-Fluorophenyl)-3-hydroxy-3-methylbutyl]-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. IV-883)

To a solution of 150 mg (0.249 mmol) of (R)-ethyl 5-{[1-(2-fluorophenyl)-3-hydroxy-3-methylbutyl]carbamoyl}-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 121 in 3 ml of dichloromethane, 0.109 ml (1.00 mmol) of N,N-dimethylethane-1,2-diamine was added in one portion with stirring at room temperature under argon stream and stirred at room temperature for 1 hour.

After the completion of the reaction, a 5% aqueous potassium bisulfate solution was added to the reaction solution, followed by extraction from the mixed solution with ethyl acetate twice. The organic layer was washed with a 5% aqueous potassium bisulfate solution, dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=70:30 to 17:83 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was dissolved in a small amount of ethyl acetate, and a solid was deposited by adding n-hexane. The solid was collected by filtration, washed with n-hexane, and dried under reduced pressure at 50° C. to obtain 112 mg of the title compound (yield: 85%) as a white solid.

Mass spectrum (CI, m/z): 530 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.20 & 11.76 (br s, total 1H), 9.72-9.46 (m, 1H), 7.54-7.43 (m, 1H), 7.26-7.17 (m, 1H), 7.17-7.04 (m, 2H), 6.62-6.47 (m, 1H), 5.23-5.14 (m, 1H), 4.78-4.62 (m, 1H), 4.55-4.35 (m, 2H), 2.58-2.40 (m, 2H), 2.27-2.12 (m, 2H), 2.02-1.73 (m, 3H), 1.67-1.45 (m, 7H), 1.18 (s, 3H), 1.15 (s, 3H), 0.09 (s, 9H).

(R)—N-(5-Hydroxy-2,5-dimethylhexan-3-yl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. IV-815)

To a solution of 99 mg (0.18 mmol) of (R)-ethyl 5-[(5-hydroxy-2,5-dimethylhexan-3-yl)carbamoyl]-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 125 in 3 ml of dichloromethane, 0.078 ml (0.72 mmol) of N,N-dimethylethane-1,2-diamine was added in one portion with stirring at room temperature under argon stream and stirred at room temperature for 1 hour.

After the completion of the reaction, a 5% aqueous potassium bisulfate solution was added to the reaction solution, followed by extraction from the mixed solution with ethyl acetate twice. The organic layer was washed with a 5% aqueous potassium bisulfate solution, dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=50:50 to 16:84 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was dissolved in a small amount of ethyl acetate, and a solid was deposited by adding n-hexane. The solid was collected by filtration, washed with n-hexane, and dried under reduced pressure at 50° C. to obtain 72 mg of the title compound (yield: 84%) as a white solid.

Mass spectrum (CI, m/z): 478 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.19 & 11.81 (br s, total 1H), 9.71-9.44 (m, 1H), 5.63 (br s, 1H), 4.47-4.25 (m, 3H), 3.71-3.60 (m, 1H), 2.57-2.39 (m, 2H), 2.27-2.11 (m, 2H), 1.90-1.66 (m, 3H), 1.65-1.52 (m, 7H), 1.49-1.42 (m, 1H), 1.10 (s, 3H), 1.09 (s, 3H), 0.82 (d, J=6.8 Hz, 6H), 0.08 (s, 9H).

N-[1-(4-Fluorophenyl)-3-hydroxy-2,2-dimethylpropyl]-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. IV-946)

To a solution of 0.745 g (1.69 mmol) of ethyl 5-(chlorocarbonyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 3 in 8 ml of 1,4-dioxane, 1.47 ml (8.44 mmol) of DIPEA and 1.00 g (5.07 mmol) of 3-amino-3-(4-fluorophenyl)-2,2-dimethylpropan-1-ol synthesized in the similar manner as in Reference Example 127 were added in this order with stirring at room temperature under argon stream and stirred at 90° C. for 1.5 hours. Subsequently, the reaction solution was allowed to cool to room temperature, and then, 0.738 ml (6.78 mmol) of N,N-dimethylethane-1,2-diamine was added dropwise at room temperature and stirred at room temperature for 4 hours.

After the completion of the reaction, a 5% aqueous potassium bisulfate solution was added to the reaction solution, followed by extraction from the mixed solution with ethyl acetate twice. The organic layer was washed with a saturated aqueous solution of sodium chloride, dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=70:30 to 19:81 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The concentration residue was dissolved in 60 ml of ethyl acetate and washed with 10 ml of a 5% aqueous potassium bisulfate solution three times. The organic layer was washed with a saturated aqueous solution of sodium chloride, dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was dissolved in a small amount of ethyl acetate, and a solid was deposited by adding n-hexane. The solid was collected by filtration, washed with n-hexane, and dried under reduced pressure at 50° C. to obtain 509 mg of the title compound (yield: 57%) as a white solid.

Mass spectrum (ESI, m/z): 530 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.21 & 11.80 (br s, total 1H), 9.68-9.44 (m, 1H), 7.39-7.32 (m, 2H), 7.17-7.09 (m, 2H), 6.91-6.78 (m, 1H), 5.46 (br s, 1H), 4.65 (d, J=7.9 Hz, 1H), 4.45-4.28 (m, 2H), 3.23 (dd, J=4.2, 10.6 Hz, 1H), 3.08-2.99 (m, 1H), 2.60-2.39 (m, 2H), 2.27-2.14 (m, 2H), 1.91-1.73 (m, 2H), 1.65-1.49 (m, 6H), 1.05 (s, 3H), 0.64 (s, 3H), 0.09 (s, 9H).

N-[1-(3-Fluorophenyl)-3-hydroxy-2,2-dimethylpropyl]-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. IV-918)

To a solution of 162 mg (0.367 mmol) of ethyl 5-(chlorocarbonyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 3 in 4 ml of 1,4-dioxane, 0.32 ml (1.9 mmol) of DIPEA and 227 mg (1.15 mmol) of 3-amino-3-(3-fluorophenyl)-2,2-dimethylpropan-1-ol synthesized in the similar manner as in Reference Example 129 were added at room temperature in an argon atmosphere and then reacted at 100° C. for 2.5 hours. After standing to cool, 0.12 ml (1.1 mmol) of N,N-dimethyl-1,2-diamine was added and stirred at room temperature for 1 hour.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure, 20 ml of ethyl acetate was added to the residue, the organic layer after washing with 10 ml of a 5% aqueous potassium bisulfate solution, 10 ml of a saturated aqueous solution of sodium bicarbonate, and 10 ml of a saturated aqueous solution of sodium chloride in this order was dried over anhydrous magnesium sulfate and filtered, and then, the filtrate was concentrated under reduced pressure. The residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: 1,2-dichloroethane:ethyl acetate=81:19 to 30:70 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was dissolved in a small amount of dichloromethane, then n-hexane was added, and the deposited solid was collected by filtration and dried under reduced pressure to obtain 159 mg of the title compound (yield: 82%) as a white solid.

Mass spectrum (CI, m/z): 530 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.22 & 11.89 (br s, total 1H), 9.79-9.40 (m, 1H), 7.39-7.29 (m, 1H), 7.22-7.13 (m, 2H), 7.08-7.01 (m, 1H), 6.86 (d, J=8.0 Hz, 1H), 5.56-5.41 (m, 1H), 4.67 (d, J=8.0 Hz, 1H), 4.49-4.27 (m, 2H), 3.25 (dd, J=4.0, 10.6 Hz, 1H), 3.05 (dd, J=4.0, 10.6 Hz, 1H), 2.56-2.40 (m, 2H), 2.29-2.13 (m, 2H), 1.92-1.72 (m, 2H), 1.60 (br s, 3H), 1.52 (br s, 3H), 1.05 (s, 3H), 0.67 (s, 3H), 0.09 (s, 9H).

(−)-N-[1-(3-Fluorophenyl)-3-hydroxy-2,2-dimethylpropyl]-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. IV-920)

0.129 g (0.244 mmol) of N-[1-(3-fluorophenyl)-3-hydroxy-2,2-dimethylpropyl]-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide synthesized in the similar manner as in Example 115 was subjected to optical resolution preparative chromatography (column: CHIRALPAK (trade name) ID, elution solvent: n-hexane:ethanol:methanol=95:5:1 (V/V)), and a fraction containing an optically active form eluted first was concentrated under reduced pressure to obtain 47 mg of the title compound (yield: 36%) as a white solid.

Specific optical rotation: [α] D 20 =−53° (c=0.23, methanol).

Mass spectrum (CI, m/z): 530 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.21 & 11.88 (br s, total 1H), 9.78-9.41 (m, 1H), 7.38-7.30 (m, 1H), 7.21-7.13 (m, 2H), 7.08-7.01 (m, 1H), 6.86 (br d, J=8.3 Hz, 1H), 5.56-5.40 (m, 1H), 4.67 (d, J=8.3 Hz, 1H), 4.47-4.30 (m, 2H), 3.25 (br dd, J=3.9, 10.5 Hz, 1H), 3.05 (br dd, J=3.9, 10.5 Hz, 1H), 2.60-2.40 (m, 2H), 2.26-2.13 (m, 2H), 1.90-1.73 (m, 2H), 1.60 (br s, 3H), 1.52 (s, 3H), 1.05 (s, 3H), 0.67 (s, 3H), 0.09 (s, 9H).

HPLC analysis:

Column: CHIRALPAK (trade name) ID 4.6×250 mm

Eluent: n-hexane/ethanol/methanol=95/5/1 (V/V)

Flow rate: 1.0 ml/min

Temperature: 40° C.

Detection wavelength: 254 nm

Retention time: 8.8 min.

Optical purity: >99% ee

(+)-N-[1-(3-Fluorophenyl)-3-hydroxy-2,2-dimethylpropyl]-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. IV-919)

A fraction containing an optically active form eluted later in the optical resolution preparative chromatography operation of Example 116 was concentrated under reduced pressure to obtain 45 mg of the title compound (yield: 35%) as a white solid.

Specific optical rotation: [α] D 20 =+59° (c=0.22, methanol).

Mass spectrum (CI, m/z): 530 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.21 & 11.94 (br s, total 1H), 9.78-9.41 (m, 1H), 7.38-7.30 (m, 1H), 7.21-7.13 (m, 2H), 7.08-7.01 (m, 1H), 6.86 (br d, J=8.1 Hz, 1H), 5.56-5.39 (m, 1H), 4.67 (d, J=8.1 Hz, 1H), 4.47-4.30 (m, 2H), 3.25 (br dd, J=3.8, 10.5 Hz, 1H), 3.05 (br dd, J=3.8, 10.5 Hz, 1H), 2.59-2.40 (m, 2H), 2.27-2.13 (m, 2H), 1.90-1.73 (m, 2H), 1.60 (br s, 3H), 1.52 (s, 3H), 1.05 (s, 3H), 0.67 (s, 3H), 0.09 (s, 9H).

HPLC analysis:

Column: CHIRALPAK (trade name) ID 4.6×250 mm

Elution solvent: n-hexane/ethanol/methanol=95/5/1 (V/V)

Flow rate: 1.0 ml/min

Temperature: 40° C.

Detection wavelength: 254 nm

Retention time: 11.6 min.

Optical purity: >98% ee

N-[1-(2-Fluorophenyl)-3-hydroxy-2,2-dimethylpropyl]-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. IV-890)

To a solution of 225 mg (1.14 mmol) of 3-amino-3-(2-fluorophenyl)-2,2-dimethylpropan-1-ol synthesized in the similar manner as in Reference Example 130 in 4 ml of 1,4-dioxane, 0.32 ml (1.9 mmol) of DIPEA and 166 mg (0.376 mmol) of ethyl 5-(chlorocarbonyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarbox amido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 3 were added at room temperature in an argon atmosphere and then reacted at 100° C. for 2.5 hours. After standing to cool, 0.12 ml (1.1 mmol) of N,N-dimethylethane-1,2-diamine was added and stirred at room temperature for 1 hour.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure, 20 ml of ethyl acetate was added to the residue, the organic layer after washing with 10 ml of a 5% aqueous potassium bisulfate solution, 10 ml of a saturated aqueous solution of sodium bicarbonate, and 10 ml of a saturated aqueous solution of sodium chloride in this order was dried over anhydrous magnesium sulfate and filtered, and then, the filtrate was concentrated under reduced pressure. The residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: 1,2-dichloroethane:ethyl acetate=81:19 to 30:70 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was dissolved in a small amount of dichloromethane, then n-hexane was added, and the deposited solid was collected by filtration and dried under reduced pressure to obtain 154 mg of the title compound (yield: 77%) as a white solid.

Mass spectrum (CI, m/z): 530 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.22 & 11.87 (br s, total 1H), 9.75-9.42 (m, 1H), 7.53-7.44 (m, 1H), 7.32-7.24 (m, 1H), 7.23-7.17 (m, 1H), 7.17-7.08 (m, 1H), 6.96-6.85 (m, 1H), 5.53 (br s, 1H), 5.03 (d, J=7.9 Hz, 1H), 4.46-4.26 (m, 2H), 3.40-3.28 (m, 1H), 3.08 (dd, J=4.0, 10.5 Hz, 1H), 2.56-2.39 (m, 2H), 2.27-2.12 (m, 2H), 1.92-1.72 (m, 2H), 1.65-1.47 (m, 6H), 1.10 (s, 3H), 0.69-0.60 (m, 3H), 0.09 (s, 9H).

N-(1-Hydroxy-2,2,4-trimethylpentan-3-yl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. IV-822)

To a solution of a mixture of 133 mg (0.246 mmol) of 2-ethyl 5-(trichloromethyl) 6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]pyrrolo[3,4-c]pyrazole-2,5(4H,6H)-dicarboxylate synthesized in the similar manner as in Reference Example 102 and 80 mg (0.18 mmol) of ethyl 5-(chlorocarbonyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate in 3 ml of dehydrated 1,4-dioxane, 0.37 ml (2.1 mmol) of DIPEA and 189 mg (1.30 mmol) of 3-amino-2,2,4-trimethylpentan-1-ol synthesized in the similar manner as in Reference Example 132 were added in this order at room temperature in an argon atmosphere and then stirred at 90° C. for 2.5 hours. After standing to cool until the reaction solution becomes room temperature, 0.23 ml (2.1 mmol) of N,N-dimethylethane-1,2-diamine was added at room temperature and stirred for 14 hours with the temperature unchanged.

After the completion of the reaction, a 5% aqueous potassium bisulfate solution was added to the reaction solution and stirred, followed by extraction with ethyl acetate three times. All of the organic layers were dried over anhydrous magnesium sulfate, then filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=60:40 to 30:70 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was dissolved in ethyl acetate, then n-hexane was added, and the deposited solid was collected by filtration, washed with n-hexane, and then dried under reduced pressure to obtain 107 mg of the title compound (yield: 52%) as a white solid.

Mass spectrum (CI, m/z): 478 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.42-11.70 (m, 1H), 9.86-9.33 (m, 1H), 5.48 (br d, J=9.2 Hz, 1H), 5.13-4.93 (m, 1H), 4.48-4.22 (m, 2H), 3.55-3.48 (m, 1H), 3.45 (dd, J=3.9, 10.7 Hz, 1H), 3.04 (dd, J=5.4, 10.7 Hz, 1H), 2.58-2.38 (m, 2H), 2.26-2.12 (m, 2H), 2.05-1.92 (m, 1H), 1.88-1.73 (m, 2H), 1.61 (br s, 3H), 1.59 (br s, 3H), 0.93 (s, 3H), 0.89 (d, J=6.7 Hz, 6H), 0.79 (s, 3H), 0.07 (s, 9H).

(R)—N-(3-Hydroxy-3-methyl-1-phenylbutyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclopropanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. III-298)

To a solution of 1.53 g (4.19 mmol) of ethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclopropanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 46 in 20 ml of dehydrated dichloromethane, 2.60 ml (14.9 mmol) of DIPEA was added at room temperature in an argon atmosphere. Subsequently, a solution of 700 mg (2.36 mmol) of bis(trichloromethyl) carbonate in 5 ml of dehydrated dichloromethane was added dropwise at −78° C. and then stirred for 0.5 hours with the temperature unchanged and further for 2 hours after the temperature was raised to room temperature.

After the completion of the reaction, a saturated aqueous solution of sodium bicarbonate and dichloromethane were added to the reaction solution at −78° C. and then stirred for 1.5 hours while the temperature was raised to room temperature for a while. The reaction solution was separated into an aqueous layer and an organic layer, and then, the aqueous layer was subjected to extraction with ethyl acetate twice. All of the organic layers were washed with a saturated aqueous solution of sodium chloride, then dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (elution solvent: n-hexane:ethyl acetate=85:15 to 75:25 (V/V)), subsequently concentrated under reduced pressure, and dried under reduced pressure to obtain 1.75 g of a white solid.

To a solution of 97.1 mg (0.542 mmol) of (R)-4-amino-2-methyl-4-phenylbutan-2-ol synthesized in the similar manner as in Reference Example 23 in 2 ml of dehydrated 1,4-dioxane, 0.18 ml (1.0 mmol) of DIPEA and 130 mg of a portion of the solid obtained by the operation described above were added in this order at room temperature in an argon atmosphere and then stirred at 90° C. for 1.5 hours.

After the completion of the reaction, a saturated aqueous solution of sodium bicarbonate was added to the reaction solution and stirred, followed by extraction with ethyl acetate three times. All of the organic layers were dried over anhydrous magnesium sulfate, then filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (elution solvent: n-hexane:ethyl acetate=70:30 to 30:70 (V/V)), subsequently concentrated under reduced pressure, and dried under reduced pressure to obtain a concentration residue.

To a solution of the obtained concentration residue in 2 ml of THF, 0.12 ml (1.1 mmol) of N,N-dimethylethane-1,2-diamine was added at room temperature in an argon atmosphere and then stirred for 2 hours with the temperature unchanged.

After the completion of the reaction, a 5% aqueous potassium bisulfate solution was added to the reaction solution and stirred, followed by extraction with ethyl acetate three times. All of the organic layers were dried over anhydrous magnesium sulfate, then filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=50:50 to 25:75 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was dissolved in ethyl acetate, then n-hexane was added, and the deposited solid was collected by filtration, washed with n-hexane, and then dried under reduced pressure to obtain 96 mg of the title compound (yield: 62% [2 steps]) as a white solid.

Mass spectrum (CI, m/z): 498 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.35-11.77 (m, 1H), 9.95-9.67 (m, 1H), 7.36-7.23 (m, 4H), 7.19-7.11 (m, 1H), 6.58-6.44 (m, 1H), 4.94-4.84 (m, 1H), 4.64 (br s, 1H), 4.40 (br s, 2H), 2.00-1.88 (m, 1H), 1.65 (dd, J=3.2, 14.2 Hz, 1H), 1.57 (br s, 3H), 1.52 (br s, 3H), 1.16 (s, 3H), 1.13 (s, 3H), 0.97 (br s, 2H), 0.98 (br s, 2H), 0.03 (s, 9H).

N-(3-Hydroxy-2,2-dimethyl-1-phenylpropyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclopropanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. III-353)

To a solution of 1.53 g (4.19 mmol) of ethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclopropanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 46 in 20 ml of dehydrated dichloromethane, 2.60 ml (14.9 mmol) of DIPEA was added at room temperature in an argon atmosphere. Subsequently, a solution of 700 mg (2.36 mmol) of bis(trichloromethyl) carbonate in 5 ml of dehydrated dichloromethane was added dropwise at −78° C. and then stirred for 0.5 hours with the temperature unchanged and further for 2 hours after the temperature was raised to room temperature.

After the completion of the reaction, a saturated aqueous solution of sodium bicarbonate and dichloromethane were added to the reaction solution at −78° C. and then stirred for 1.5 hours while the temperature was raised to room temperature for a while. The reaction solution was separated into an aqueous layer and an organic layer, and then, the aqueous layer was subjected to extraction with ethyl acetate twice. All of the organic layers were washed with a saturated aqueous solution of sodium chloride, then dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (elution solvent: n-hexane:ethyl acetate=85:15 to 75:25 (V/V)), subsequently concentrated under reduced pressure, and dried under reduced pressure to obtain 1.75 g of a white solid.

To a solution of 109 mg (0.608 mmol) of 3-amino-2,2-dimethyl-3-phenylpropan-1-ol [synthesized according to the method described in Synthetic Communications 1994, 24 (7), 899-906] in 2 ml of dehydrated 1,4-dioxane, 0.20 ml (1.1 mmol) of DIPEA and 142 mg of a portion of the solid obtained by the operation described above were added in this order at room temperature in an argon atmosphere and then stirred at 90° C. for 2.5 hours. After standing to cool until the reaction solution becomes room temperature, 0.13 ml (1.2 mmol) of N,N-dimethylethane-1,2-diamine was added at room temperature and stirred for 2 hours with the temperature unchanged.

After the completion of the reaction, a 5% aqueous potassium bisulfate solution was added to the reaction solution and stirred, followed by extraction with ethyl acetate three times. All of the organic layers were dried over anhydrous magnesium sulfate, then filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=60:40 to 40:60 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was dissolved in ethyl acetate, then n-hexane was added, and the deposited solid was collected by filtration, washed with n-hexane, and then dried under reduced pressure to obtain 112 mg of the title compound (yield: 66% [2 steps]) as a white solid.

Mass spectrum (CI, m/z): 498 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.40-11.84 (m, 1H), 10.11-9.58 (m, 1H), 7.37-7.26 (m, 4H), 7.25-7.18 (m, 1H), 6.85 (br d, J=8.2 Hz, 1H), 5.53-5.39 (m, 1H), 4.63 (d, J=8.2 Hz, 1H), 4.45-4.25 (m, 2H), 3.29-3.22 (m, 1H), 3.07-2.98 (m, 1H), 1.58 (s, 3H), 1.51 (s, 3H), 1.06 (s, 3H), 1.03-0.94 (m, 2H), 0.76-0.58 (m, 5H), 0.03 (s, 9H).

(−)-N-(3-Hydroxy-2,2-dimethyl-1-phenylpropyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. IV-673)

To a solution of a mixture of 545 mg (1.16 mmol) of 2-ethyl 5-(trichloromethyl) 6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]pyrrolo[3,4-c]pyrazole-2,5(4H,6H)-dicarboxylate synthesized in the similar manner as in Reference Example 102 and 329 mg (0.853 mmol) of ethyl 5-(chlorocarbonyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate in 7 ml of dehydrated 1,4-dioxane, 1.80 ml (10.3 mmol) of DIPEA and 1.16 g (6.47 mmol) of 3-amino-2,2-dimethyl-3-phenylpropan-1-ol [synthesized according to the method described in Synthetic Communications 1994, 24 (7), 899-906] were added in this order at room temperature in an argon atmosphere and then stirred at 90° C. for 2 hours. After standing to cool until the reaction solution becomes room temperature, 0.90 ml (8.3 mmol) of N,N-dimethylethane-1,2-diamine was added at room temperature and stirred for 2.5 hours with the temperature unchanged.

After the completion of the reaction, a 5% aqueous potassium bisulfate solution was added to the reaction solution and stirred, followed by extraction with ethyl acetate three times. All of the organic layers were dried over anhydrous magnesium sulfate, then filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=60:40 to 40:60 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was subjected again to silica gel column chromatography (DIOL silica gel, elution solvent: 1,2-dichloroethane:ethyl acetate=100:0 to 85:15 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was dissolved in an ethyl acetate/ethanol mixed solvent, then n-hexane was added, and the deposited solid was collected by filtration, washed with n-hexane, and then dried under reduced pressure to obtain 802 mg of a white solid.

0.50 g of a portion of the obtained solid was subjected to optical resolution preparative chromatography (column: CHIRALPAK (trade name) ID, elution solvent: n-hexane:ethanol=90:10 (V/V)), and a fraction containing an optically active form eluted first was concentrated under reduced pressure. The obtained concentration residue was dissolved in an acetonitrile/water mixed solvent and then freeze-dried to obtain 225 mg of the title compound (yield: 35%) as a white solid.

Specific optical rotation: [α] D 20 =−66° (c=0.50, methanol).

Mass spectrum (CI, m/z): 512 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.35-11.77 (m, 1H), 9.86-9.35 (m, 1H), 7.36-7.27 (m, 4H), 7.25-7.17 (m, 1H), 6.86 (br d, J=8.2 Hz, 1H), 5.45 (br s, 1H), 4.64 (d, J=8.2 Hz, 1H), 4.46-4.30 (m, 2H), 3.45-3.23 (m, 1H), 3.06-2.99 (m, 1H), 2.58-2.40 (m, 2H), 2.26-2.14 (m, 2H), 1.90-1.73 (m, 2H), 1.60 (s, 3H), 1.52 (s, 3H), 1.06 (s, 3H), 0.64 (s, 3H), 0.09 (s, 9H).

SFC (supercritical fluid chromatography) analysis:

Column: CHIRALPAK (trade name) ID 2.1×150 mm (particle size: 3 um)

Eluent: CO 2 /methanol=90/10 (V/V)

Flow rate: 0.85 ml/min

Temperature: 40° C.

Detection wavelength: 240 nm

Retention time: 5.3 min.

Optical purity: >99% ee

(+)-N-(3-Hydroxy-2,2-dimethyl-1-phenylpropyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. IV-672)

A fraction containing an optically active form eluted later in the optical resolution preparative chromatography operation of Example 122 was concentrated under reduced pressure. The obtained concentration residue was dissolved in an acetonitrile/water mixed solvent and then freeze-dried to obtain 223 mg of the title compound (yield: 35%) as a white solid.

Specific optical rotation: [α] D 20 =+60° (c=0.50, methanol).

Mass spectrum (CI, m/z): 512 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.42-11.76 (m, 1H), 9.57 (br s, 1H), 7.35-7.27 (m, 4H), 7.25-7.18 (m, 1H), 6.86 (br d, J=8.2 Hz, 1H), 5.45 (br s, 1H), 4.64 (d, J=8.2 Hz, 1H), 4.44-4.30 (m, 2H), 3.44-3.23 (m, 1H), 3.06-2.98 (m, 1H), 2.59-2.40 (m, 2H), 2.26-2.14 (m, 2H), 1.89-1.74 (m, 2H), 1.60 (s, 3H), 1.52 (s, 3H), 1.06 (s, 3H), 0.64 (s, 3H), 0.09 (s, 9H).

SFC (supercritical fluid chromatography) analysis:

Column: CHIRALPAK (trade name) ID 2.1×150 mm (particle size: 3 um)

Eluent: CO 2 /methanol=90/10 (V/V)

Flow rate: 0.85 ml/min

Temperature: 40° C.

Detection wavelength: 240 nm

Retention time: 6.5 min.

Optical purity: >99% ee

(R)—N-[5-(2-Butoxy-2-phenylacetyl)-6,6-dimethyl-1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazol-3-yl]-1-(trimethylsilyl)cyclobutanecarboxamide (Compound No. IV-1200)

To a solution of 1.65 g (5.53 mmol) of (R)-benzyl 2-butoxy-2-phenylacetate synthesized in the similar manner as in Reference Example 133 in 8 ml of methanol/8 ml of water, 300 mg (7.15 mmol) of lithium hydroxide monohydrate was added at room temperature and then reacted with stirring at room temperature for 3 hours.

After the completion of the reaction, diethyl ether was added to the reaction solution and separated into an aqueous layer and an organic layer. The aqueous layer was adjusted to pH 2 by adding 2 N hydrochloric acid, followed by extraction with ethyl acetate three times. All of the obtained organic layers were washed with saturated saline, then dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure to obtain 1.34 g of a concentration residue.

To a solution of 150 mg of a portion of the obtained concentration residue in 2 ml of dehydrated dichloromethane, 0.006 ml (0.08 mmol) of DMF and 0.083 ml (0.95 mmol) of oxalyl chloride were added with stirring at 0° C. in an argon atmosphere and stirred at room temperature for 1.5 hours.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure to obtain a concentration residue.

To a solution of 150 mg (0.396 mmol) of ethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 84 and 0.350 ml (2.00 mmol) of DIPEA in 2 ml of dehydrated dichloromethane, a solution of the obtained concentration residue in 3 ml of dehydrated dichloromethane was added dropwise with stirring at 0° C. in an argon atmosphere and stirred at room temperature for 3 hours.

After the completion of the reaction, a saturated aqueous solution of sodium bicarbonate was added to the reaction solution, followed by extraction with dichloromethane. The obtained organic layer was washed with water, then dried over anhydrous sodium sulfate, and filtered, and the filtrate was concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=100:0 to 70:30 (V/V)) and subsequently concentrated under reduced pressure to obtain a concentration residue.

To a solution of the obtained concentration residue in 2 ml of dehydrated dichloromethane, 0.130 ml (1.19 mmol) of N,N-dimethylethane-1,2-diamine was added at room temperature in an argon atmosphere and then stirred at room temperature for 16 hours.

After the completion of the reaction, a 5% aqueous potassium bisulfate solution was added to the reaction solution and stirred, followed by extraction with dichloromethane. The obtained organic layer was washed with a saturated aqueous solution of sodium bicarbonate and saturated saline in this order, then dried over anhydrous sodium sulfate, and filtered, and the filtrate was concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=100:0 to 50:50 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was subjected to preparative HPLC (column: X-Bridge (trade name) ODS, elution solvent: acetonitrile:1 mM aqueous potassium dihydrogen phosphate solution=50:50 (V/V)), and ethyl acetate and water were added to a fraction containing the compound of interest to separate an organic layer and an aqueous layer. The obtained organic layer was concentrated under reduced pressure. The obtained concentration residue was dissolved in ethyl acetate and then added to n-hexane, and the deposited solid was collected by filtration and dried under reduced pressure to obtain 77 mg of the title compound (yield: 39%) as a white solid.

Mass spectrum (CI, m/z): 497 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.34-11.89 (m, 1H), 9.56 (br s, 1H), 7.45-7.25 (m, 5H), 5.02 (s, 1H), 4.68-4.49 (m, 1H), 4.40 (br d, J=12.7 Hz, 1H), 3.57-3.39 (m, 2H), 2.59-2.35 (m, 2H), 2.24-2.09 (m, 2H), 1.87-1.73 (m, 2H), 1.68 (s, 3H), 1.61 (s, 3H), 1.56-1.45 (m, 2H), 1.40-1.28 (m, 2H), 0.86 (t, J=7.3 Hz, 3H), 0.05 (s, 9H).

N-(3-Methoxy-2,2-dimethyl-1-phenylpropyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-4,6-dihydropyrrolo[3,4-c]pyrazole-5(1H)-carboxamide (Compound No. IV-676)

To a solution of 131 mg (0.219 mmol) of ethyl 5-[(3-methoxy-2,2-dimethyl-1-phenylpropyl)carbamoyl]-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 137 in 3 ml of dichloromethane, 0.095 ml (0.87 mol) of N,N-dimethylethane-1,2-diamine was added in one portion with stirring at room temperature under argon stream and stirred at room temperature for 1 hour.

After the completion of the reaction, a 5% aqueous potassium bisulfate solution was added to the reaction solution, followed by extraction from the mixed solution with ethyl acetate twice. The organic layer was washed with a 5% aqueous potassium bisulfate solution, dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (DIOL silica gel, elution solvent: n-hexane:ethyl acetate=70:30 to 13:87 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was dissolved in a small amount of ethyl acetate, and a solid was deposited by adding n-hexane. The solid was collected by filtration, washed with n-hexane, and dried under reduced pressure at 50° C. to obtain 62 mg of the title compound (yield: 54%) as a white solid.

Mass spectrum (CI, m/z): 526 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 12.21 & 11.76 (br s, total 1H), 9.58 (br s, 1H), 7.38-7.18 (m, 5H), 6.75-6.52 (m, 1H), 4.59 (d, J=7.7 Hz, 1H), 4.52-4.30 (m, 2H), 3.38 (s, 3H), 3.13 (d, J=9.3 Hz, 1H), 2.92 (d, J=9.3 Hz, 1H), 2.58-2.40 (m, 2H), 2.29-2.12 (m, 2H), 1.91-1.74 (m, 2H), 1.59 (br s, 3H), 1.50 (s, 3H), 1.12 (s, 3H), 0.68 (s, 3H), 0.09 (s, 9H).

Reference Example 1

1-(Trimethylsilyl)cyclobutanecarboxylic acid

To 200 ml of dehydrated THF, 214 ml (428 mmol) of 2 M lithium diisopropylamide/THF solution was added in an argon atmosphere, and then, 10.1 ml (107 mmol) of cyclobutanecarboxylic acid was added dropwise with stirring under cooling in ice water and stirred for 4 hours while the temperature was raised to room temperature for a while. Subsequently, 20 ml (116 mmol) of hexamethylphosphoric acid triamide was added, and 51 ml (490 mmol) of chlorotrimethylsilane was added dropwise with stirring while the internal temperature was kept at −60° C. or lower under cooling in a dry ice/acetone coolant, and then stirred at −78° C. for 16.5 hours.

After the completion of the reaction, 67 ml of methanol was added to the reaction solution, and 134 ml of cold water was added after the temperature was raised to 0° C. The pH was adjusted to 2.1 by adding 2 N hydrochloric acid, 268 ml of diethyl ether was added thereto and then the aqueous layer and the organic layer were separated, and the organic layer was washed with 268 ml of a saturated aqueous solution of sodium chloride. The organic layer was dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. 50 ml of a 2 N aqueous sodium hydroxide solution and 267 ml of n-hexane were added to the obtained concentration residue and then the aqueous layer and the organic layer were separated. Subsequently, the aqueous layer was adjusted to pH 2.7 by adding 1 N hydrochloric acid, and 267 ml of ethyl acetate was added to this solution and then the aqueous layer and the organic layer were separated. The obtained organic layer was dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. n-Hexane was added to the obtained concentration residue and cooled in an ice water bath. The resulting solid was filtered, washed by sousing with cooled n-hexane, and then dried under reduced pressure to obtain 6.24 g of the title compound (yield: 34%) as a white solid. The filtrate was further concentrated under reduced pressure, and the obtained residue was subjected to silica gel column chromatography (elution solvent: 1,2-dichloroethane:methanol=100:0 to 95:5 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure and dried under reduced pressure to obtain 4.33 g of the title compound (yield: 23%) as a white solid.

Mass spectrum (CI, m/z): 173 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 11.64 (br s, 1H), 2.45-2.34 (m, 2H), 2.17-2.06 (m, 2H), 1.91-1.70 (m, 2H), 0.06 (s, 9H).

Reference Example 2

5-tert-Butyl 2-ethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]pyrrolo[3,4-c]pyrazole-2,5(4H,6H)-dicarboxylate

To a solution of 13.9 g (80.4 mmol) of 1-(trimethylsilyl)cyclobutanecarboxylic acid synthesized in the similar manner as in Reference Example 1 in 105 ml of dehydrated dichloromethane, 6.96 ml (81.2 mmol) of oxalyl chloride and 0.32 ml (4.14 mmol) of DMF were added dropwise in this order between −25° C. and −10° C. in an argon atmosphere and then stirred for 2 hours after the temperature was raised to 0° C. To a solution of 8.74 g (26.9 mmol) of 5-tert-butyl 2-ethyl 3-amino-6,6-dimethylpyrrolo[3,4-c]pyrazole-2,5(4H,6H)-dicarboxylate [synthesized according to the method described in Journal of Medicinal Chemistry 2012, 55 (10), 4728-4739] and 23.5 ml (135 mmol) of DIPEA in 122 ml of dehydrated dichloromethane, the resulting reaction solution was added dropwise at 0° C. in an argon atmosphere and stirred at the same temperature as above for 16 hours.

After the completion of the reaction, 486 ml of a 5% aqueous potassium bisulfate solution was added to the reaction solution and then the aqueous layer and the organic layer were separated. The aqueous layer was subjected to extraction with 200 ml of dichloromethane twice. All of the obtained organic layers were dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (elution solvent: n-hexane:ethyl acetate=86:14 to 53:47 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure and dried under reduced pressure to obtain 8.30 g of the title compound (yield: 64%) as a white foam.

Mass spectrum (CI, m/z): 479 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 9.98 & 9.72 & 9.71 (s, total 1H), 4.50-4.37 (m, 4H), 2.53-2.43 (m, 2H), 2.32-2.07 (m, 2H), 2.02-1.72 (m, 2H), 1.65-1.55 (m, 6H), 1.51-1.42 (m, 9H), 1.38-1.31 (m, 3H), 0.10 & 0.06 & 0.01 (s, total 9H).

Reference Example 3

Ethyl 5-(chlorocarbonyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate

To a solution of 8.30 g (17.3 mmol) of 5-tert-butyl 2-ethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]pyrrolo[3,4-c]pyrazole-2,5(4H,6H)-dicarboxylate synthesized in the similar manner as in Reference Example 2 in 81 ml of dehydrated dichloromethane, 6.0 ml (52 mmol) of 2,6-lutidine and 9.2 ml (51 mmol) of trimethylsilyl trifluoromethanesulfonate were added dropwise in this order at 0° C. in an argon atmosphere and stirred at the same temperature as above for 2 hours.

After the completion of the reaction, 64 ml of a saturated aqueous solution of sodium bicarbonate and 64 ml of dichloromethane were added to the reaction solution and then the aqueous layer and the organic layer were separated. The aqueous layer was subjected to extraction with 72 ml of dichloromethane twice, and then, all of the obtained organic layers were washed with 72 ml of a saturated aqueous solution of sodium bicarbonate and 72 ml of a saturated aqueous solution of sodium chloride in this order, subsequently dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The operation of adding 5 ml of toluene to the obtained concentration residue and concentrating the resultant under reduced pressure was repeated five times to obtain crude ethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate.

To a solution of 6.70 g of the obtained crude ethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate in 235 ml of dehydrated dichloromethane, 8.8 ml (51 mmol) of DIPEA was added at room temperature in an argon atmosphere, and then, a solution of 3.79 g (12.8 mmol) of bis(trichloromethyl)carbonate in 38 ml of dehydrated dichloromethane was added dropwise at −78° C. and stirred at the same temperature as above for 3 hours. At each point in time of 1 hour, 2 hours, and 2.6 hours after the start of this reaction, 1.0 ml (5.7 mmol) of DIPEA was added thereto.

After the completion of the reaction, 150 ml of a saturated aqueous solution of sodium bicarbonate was added to the reaction solution and stirred while the temperature was raised to room temperature for a while. After separation into an aqueous layer and an organic layer, the aqueous layer was subjected to extraction with 130 ml of dichloromethane twice. All of the obtained organic layers were dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (elution solvent: n-hexane:ethyl acetate=78:22 to 57:43 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. n-Hexane was added to the obtained concentration residue and ultrasonicated. After cooling in a refrigerator, the deposited solid was filtered and dried under reduced pressure to obtain 3.51 g of the title compound (yield: 46% [2 steps]) as a white solid.

Mass spectrum (CI, m/z): 441 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 9.83-9.65 (m, 1H), 4.84 (s, 2H), 4.49-4.37 (m, 2H), 2.54-2.43 (m, 2H), 2.31-2.21 (m, 2H), 1.95-1.83 (m, 2H), 1.71-1.58 (m, 6H), 1.35 (t, J=7.1 Hz, 3H), 0.13-0.08 (m, 9H).

Reference Example 4

5-tert-Butyl 1-ethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]pyrrolo[3,4-c]pyrazole-1,5(4H,6H)-dicarboxylate

To a solution of 24.52 g (142 mmol) of 1-(trimethylsilyl)cyclobutanecarboxylic acid synthesized in the similar manner as in Reference Example 1 in 180 ml of dehydrated dichloromethane, 0.55 ml (7.1 mmol) of DMF and 12.2 ml (142 mmol) of oxalyl chloride were added dropwise at 0° C. in an argon atmosphere and stirred at the same temperature as above for 2 hours.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure (hot water bath temperature: 30° C.) to obtain a concentration residue.

To a solution of 15.39 g (47.4 mmol) of 5-tert-butyl 1-ethyl 3-amino-6,6-dimethylpyrrolo[3,4-c]pyrazole-1,5(4H,6H)-dicarboxylate [synthesized according to the method described in Journal of Medicinal Chemistry 2012, 55 (10), 4728-4739] and 40.6 ml (238 mmol) of DIPEA in 180 ml of dehydrated dichloromethane, a solution of the obtained concentration residue in 120 ml of dehydrated dichloromethane was added dropwise at 0° C. in an argon atmosphere and stirred at the same temperature as above for 20 hours.

After the completion of the reaction, the reaction solution was poured to 800 ml of a 5% aqueous potassium bisulfate solution, stirred, and then the aqueous layer and the organic layer were separated. The aqueous layer was subjected to extraction with 250 ml of dichloromethane twice. All of the obtained organic layers were dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (elution solvent: n-hexane:ethyl acetate=91:9 to 70:30 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure and dried under reduced pressure to obtain 14.6 g of the title compound (yield: 64%) as a white foam.

Mass spectrum (EI, m/z): 478 [M] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 10.32-10.20 (m, 1H), 4.46-4.32 (m, 4H), 2.48-2.39 (m, 2H), 2.24-2.14 (m, 2H), 1.84-1.68 (m, 8H), 1.52-1.40 (m, 9H), 1.32 (t, J=7.1 Hz, 3H), 0.07 (s, 9H).

Reference Example 5

Ethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-1(4H)-carboxylate

To a solution of 10.02 g (20.9 mmol) of 5-tert-butyl 1-ethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]pyrrolo[3,4-c]pyrazole-1,5(4H,6H)-dicarboxylate synthesized in the similar manner as in Reference Example 4 in 100 ml of dehydrated dichloromethane, 7.26 ml (62.7 mmol) of 2,6-lutidine and 11.3 ml (62.7 mmol) of trimethylsilyl trifluoromethanesulfonate were added dropwise at 0° C. in an argon atmosphere and stirred at the same temperature as above for 1.5 hours.

After the completion of the reaction, 60 ml of a saturated aqueous solution of sodium bicarbonate and 60 ml of dichloromethane were added to the reaction solution. After separation into an aqueous layer and an organic layer, the aqueous layer was subjected to extraction with 60 ml of dichloromethane twice. All of the obtained organic layers were washed with 60 ml of a saturated aqueous solution of sodium bicarbonate and 60 ml of a saturated aqueous solution of sodium chloride in this order, then dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The operation of adding toluene to the obtained concentration residue and concentrating it under reduced pressure was repeated three times to obtain 7.43 g of the title compound (yield: 94%) as a pale yellow solid.

Mass spectrum (EI, m/z): 378 [M] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 10.03 (s, 1H), 4.37 (q, J=7.1 Hz, 2H), 3.85 (s, 2H), 2.48-2.38 (m, 2H), 2.23-2.12 (m, 2H), 1.85-1.72 (m, 2H), 1.41 (s, 6H), 1.31 (t, J=7.1 Hz, 3H), 0.06 (s, 9H).

Reference Example 6

5-tert-Butyl 2-ethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclopropanecarboxamido]pyrrolo[3,4-c]pyrazole-2,5(4H,6H)-dicarboxylate

To a solution of 1.05 g (6.63 mmol) of 1-(trimethylsilyl)cyclopropanecarboxylic acid [synthesized according to the method described in J. Org. Chem., 1982, 47 (5), 893-895] in 20 ml of dehydrated dichloromethane, 0.70 ml (8.2 mmol) of oxalyl chloride and 0.020 ml (0.26 mmol) of DMF were added at 0° C. in a nitrogen atmosphere and stirred at the same temperature as above for 3 hours.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure (hot water bath temperature: 25° C.) to obtain a concentration residue.

To a solution of the obtained concentration residue in 15 ml of dehydrated dichloromethane, 1.80 ml (10.3 mmol) of DIPEA and 839 mg (2.59 mmol) of 5-tert-butyl 2-ethyl 3-amino-6,6-dimethylpyrrolo[3,4-c]pyrazole-2,5(4H,6H)-dicarboxylate [synthesized according to the method described in Journal of Medicinal Chemistry 2012, 55 (10), 4728-4739] were added at 0° C. in a nitrogen atmosphere and stirred at the same temperature as above for 20.5 hours.

After the completion of the reaction, a saturated aqueous solution of sodium bicarbonate was added to the reaction solution, followed by extraction with dichloromethane twice. All of the obtained organic layers were dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (elution solvent: n-hexane:ethyl acetate=90:10 to 75:25 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure and dried under reduced pressure to obtain 1.19 g of the title compound (containing impurities) as a pale yellow foam.

Mass spectrum (CI, m/z): 465 [M+1] + .

1 H-NMR spectrum (400 MHz, CDCl 3 ) δ: 10.09 & 9.92 (s, total 1H), 4.70-4.46 (m, 4H), 1.72 (s, 3H), 1.65 (s, 3H), 1.54-1.44 (m, 12H), 1.15-1.07 (m, 2H), 0.84-0.78 (m, 2H), 0.17-0.07 (m, 9H).

Reference Example 7

Ethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclopropanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate hydrochloride

To a solution of 1.19 g of 5-tert-butyl 2-ethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclopropanecarboxamido]pyrrolo[3,4-c]pyrazole-2,5(4H,6H)-dicarboxylate (containing impurities) synthesized in the similar manner as in Reference Example 6 in 20 ml of ethyl acetate, 4.0 ml (16 mmol) of 4 N hydrogen chloride/ethyl acetate was added at room temperature in a nitrogen atmosphere and stirred at the same temperature as above for 6.5 hours. Then, 2.0 ml (8.0 mmol) of 4 N hydrogen chloride/ethyl acetate was added thereto and further stirred at room temperature for 14.5 hours.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure, and the obtained concentration residue was suspended in diisopropyl ether and stirred at room temperature. Insoluble matter was collected by filtration, and the obtained solid was washed by sousing with diisopropyl ether and then dried under reduced pressure to obtain 0.91 g of the title compound (yield: 88% [2 steps]) as a white solid.

Mass spectrum (CI, m/z): 365 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 9.99 (br s, 2H), 9.91 (s, 1H), 4.51-4.39 (m, 4H), 1.63 (s, 6H), 1.35 (t, J=7.2 Hz, 3H), 1.08 (dd, J=4.2, 6.0 Hz, 2H), 0.87 (dd, J=4.2, 6.0 Hz, 2H), 0.08 (s, 9H).

Reference Example 8

2-Methyl-2-(trimethylsilyl)propanoic acid

To 100 ml of dehydrated THF, 200 ml (400 mmol) of 2 M lithium diisopropylamide/THF solution was added in an argon atmosphere, and subsequently, 4.7 ml (51 mmol) of isobutanoic acid was added dropwise at 0° C. and then stirred at room temperature for 4 hours. 10 ml (58 mmol) of hexamethylphosphoric acid triamide was added thereto, and then, 29 ml (230 mmol) of chlorotrimethylsilane was added thereto dropwise at −78° C. and stirred for 24 hours while the temperature was gradually raised to room temperature.

After the completion of the reaction, 25 ml of methanol and 50 ml of water were added to the reaction solution. Subsequently, the solution was rendered acidic by adding 2 N hydrochloric acid, followed by extraction with diethyl ether. All of the obtained organic layers were washed with a saturated aqueous solution of sodium chloride, then dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was dissolved in a 2 N aqueous sodium hydroxide solution and washed with ethyl acetate. After separation into an aqueous layer and an organic layer, the aqueous layer was rendered acidic by adding 1 N hydrochloric acid, followed by extraction with ethyl acetate. All of the obtained organic layers were dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was suspended in n-hexane, and after ultrasonication, insoluble matter was collected by filtration. The filtrate was concentrated under reduced pressure, the obtained concentration residue was subjected to silica gel column chromatography (elution solvent: 1,2-dichloroethane:methanol=100:0 to 99:1 (V/V)), and a fraction containing the compound of interest and the aforementioned solid collected by filtration were combined, concentrated under reduced pressure, and dried under reduced pressure to obtain 2.66 g of the title compound (yield: 32%) as a white solid.

Mass spectrum (CI, m/z): 161 [M+1] + .

1 H-NMR spectrum (400 MHz, CDCl 3 ) δ: 1.22 (s, 6H), 0.08 (s, 9H).

Reference Example 9

5-tert-Butyl 1-ethyl 6,6-dimethyl-3-[2-methyl-2-(trimethylsilyl)propanamido]pyrrolo[3,4-c]pyrazole-1,5(4H,6H)-dicarboxylate

To a solution of 1.30 g (8.11 mmol) of 2-methyl-2-(trimethylsilyl)propanoic acid synthesized in the similar manner as in Reference Example 8 in 25 ml of dehydrated dichloromethane, 0.85 ml (9.9 mmol) of oxalyl chloride and 0.040 ml (0.52 mmol) of DMF were added in this order at 0° C. in a nitrogen atmosphere and stirred at the same temperature as above for 3.5 hours.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure (hot water bath temperature: 25° C.) to obtain a concentration residue.

To a solution of the obtained concentration residue in 15 ml of dehydrated dichloromethane, 2.30 ml (13.2 mmol) of DIPEA and 1.08 g (3.33 mmol) of 5-tert-butyl 1-ethyl 3-amino-6,6-dimethylpyrrolo[3,4-c]pyrazole-1,5(4H,6H)-dicarboxylate [synthesized according to the method described in Journal of Medicinal Chemistry 2012, 55 (10), 4728-4739] were added in this order at 0° C. in a nitrogen atmosphere and stirred at the same temperature as above for 17.5 hours.

After the completion of the reaction, a saturated aqueous solution of sodium bicarbonate was added to the reaction solution and stirred, followed by extraction with dichloromethane three times. All of the organic layers were dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (elution solvent: n-hexane:ethyl acetate=93:7 to 80:20 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure and dried under reduced pressure to obtain 1.28 g of the title compound (yield: 82%) as a pale yellow foam.

Mass spectrum (CI, m/z): 467 [M+1] + .

1 H-NMR spectrum (400 MHz, CDCl 3 ) δ: 7.87-7.74 (m, 1H), 4.60-4.47 (m, 4H), 1.84 & 1.78 (s, total 6H), 1.55-1.48 (m, 9H), 1.47 (t, J=7.2 Hz, 3H), 1.31-1.25 (m, 6H), 0.10-0.04 (m, 9H).

Reference Example 10

1-(Ethyldimethylsilyl)cyclobutanecarboxylic acid

To 200 ml of dehydrated THF, 214 ml (428 mmol) of 2 M lithium diisopropylamide/THF solution was added in an argon atmosphere, and then, 10.7 ml (112 mmol) of cyclobutanecarboxylic acid was added dropwise under cooling in ice water and stirred while the temperature was raised to room temperature for a while. Subsequently, 20 ml (120 mmol) of hexamethylphosphoric acid triamide was added. After cooling in a dry ice/ethanol coolant, 67.6 ml (485 mmol) of chloro(ethyl)dimethylsilane was added dropwise at −75° C. to −69° C. and stirred overnight at a temperature of −60° C. or lower.

After the completion of the reaction, 67 ml of methanol and subsequently 134 ml of cold water were added dropwise to the reaction solution and then brought to room temperature. 240 ml of 2 N hydrochloric acid was added for acidity (pH 2.0), and 200 ml of diethyl ether was added thereto and then the aqueous layer and the organic layer were separated. The obtained organic layer was washed with 250 ml of a saturated aqueous solution of sodium chloride, then dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. 41 ml of a 2 N aqueous sodium hydroxide solution was added to the obtained concentration residue and washed with 250 ml of n-hexane. The aqueous layer was rendered acidic (pH 2.0) again by adding 82 ml of 1 N hydrochloric acid. This solution was subjected to extraction with 250 ml of ethyl acetate, and the organic layer was concentrated under reduced pressure. The obtained residue was subjected to silica gel column chromatography (elution solvent: 1,2-dichloroethane:methanol=100:0 to 95:5 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure and dried under reduced pressure to obtain 11.7 g of the title compound (yield: 59%) as a white solid.

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 11.71 (br s, 1H), 2.44-2.33 (m, 2H), 2.19-2.08 (m, 2H), 1.91-1.73 (m, 2H), 0.92 (t, J=7.9 Hz, 3H), 0.55 (q, J=7.9 Hz, 2H), 0.05 (s, 6H).

Reference Example 11

5-tert-Butyl 2-ethyl 3-[1-(ethyldimethylsilyl)cyclobutanecarboxamido]-6,6-dimethylpyrrolo[3,4-c]pyrazole-2,5(4H,6H)-dicarboxylate

To a solution of 11.7 g (62.8 mmol) of 1-(ethyldimethylsilyl)cyclobutanecarboxylic acid synthesized in the similar manner as in Reference Example 10 in 81 ml of dehydrated dichloromethane, 5.3 ml (62 mmol) of oxalyl chloride and 0.24 ml (3.1 mmol) of DMF were added in this order under cooling in ice water in an argon atmosphere and stirred at the same temperature as above for 2 hours.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure at room temperature to obtain a concentration residue.

To a solution of 6.73 g (20.7 mmol) of 5-tert-butyl 2-ethyl 3-amino-6,6-dimethylpyrrolo[3,4-c]pyrazole-2,5(4H,6H)-dicarboxylate [synthesized according to the method described in Journal of Medicinal Chemistry 2012, 55 (10), 4728-4739] and 18 ml (100 mmol) of DIPEA in 94 ml of dehydrated dichloromethane, a solution of the obtained concentration residue in 5 ml of dehydrated dichloromethane was added dropwise under cooling in ice water in a nitrogen atmosphere and stirred at the same temperature as above for 16 hours.

After the completion of the reaction, 350 ml of a 5% aqueous potassium bisulfate solution was added to the reaction solution and separated into an aqueous layer and an organic layer, and then, the aqueous layer was subjected to extraction with 150 ml of dichloromethane twice. All of the obtained organic layers were dried over anhydrous magnesium sulfate and then filtered, and the filtrate was concentrated under reduced pressure. The obtained residue was subjected to silica gel column chromatography (elution solvent: n-hexane:ethyl acetate=86:14 to 53:47 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure to obtain 7.51 g of the title compound (yield: 74%) as a pale yellow oil.

Mass spectrum (DUIS, m/z): 493 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 9.82-9.69 (m, 1H), 4.51-4.36 (m, 4H), 2.49-2.42 (m, 2H), 2.32-2.23 (m, 2H), 1.95-1.84 (m, 2H), 1.62-1.55 (m, 6H), 1.49-1.42 (m, 9H), 1.38-1.31 (m, 3H), 0.91 (t, J=7.9 Hz, 3H), 0.57 (q, J=7.9 Hz, 2H), 0.09 (s, 6H).

Reference Example 12

Ethyl 3-[1-(ethyldimethylsilyl)cyclobutanecarboxamido]-6,6-dimethyl-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate

To a solution of 7.27 g (14.8 mmol) of 5-tert-butyl 2-ethyl 3-[1-(ethyldimethylsilyl)cyclobutanecarboxamido]-6,6-dimethylpyrrolo[3,4-c]pyrazole-2,5(4H,6H)-dicarboxylate synthesized in the similar manner as in Reference Example 11 in 70 ml of dehydrated dichloromethane, 5.1 ml (44 mmol) of 2,6-lutidine and 7.8 ml (43 mmol) of trimethylsilyl trifluoromethanesulfonate were added dropwise in this order under ice cooling in an argon atmosphere and stirred at the same temperature as above for 2 hours.

After the completion of the reaction, 57 ml of a saturated aqueous solution of sodium bicarbonate and 57 ml of dichloromethane were added to the reaction solution, and then the aqueous layer and the organic layer were separated. The aqueous layer was subjected to extraction with 60 ml of dichloromethane twice, all of the obtained organic layers were washed with 60 ml of a saturated aqueous solution of sodium bicarbonate and 60 ml of a saturated aqueous solution of sodium chloride in this order, then dried over anhydrous magnesium sulfate, and filtered, and the filtrate was concentrated under reduced pressure. The operation of adding toluene to the obtained concentration residue and concentrating the resultant under reduced pressure was performed five times to obtain 5.92 g of the title compound (containing impurities) as a yellow oil.

Mass spectrum (DUIS, m/z): 393 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 9.68 (s, 1H), 4.39 (q, J=7.0 Hz, 2H), 3.92 (s, 2H), 2.48-2.40 (m, 2H), 2.29-2.22 (m, 2H), 1.93-1.82 (m, 2H), 1.33 (t, J=7.0 Hz, 3H), 1.29 (s, 6H), 0.91 (t, J=8.1 Hz, 3H), 0.56 (q, J=8.1 Hz, 2H), 0.08 (s, 6H).

Reference Example 13

Ethyl 5-(chlorocarbonyl)-3-[1-(ethyldimethylsilyl)cyclobutanecarboxamido]-6,6-dimethyl-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate

To a solution of 5.92 g of ethyl 3-[1-(ethyldimethylsilyl)cyclobutanecarboxamido]-6,6-dimethyl-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate (containing impurities) synthesized in the similar manner as in Reference Example 12 by using 7.27 g (14.8 mmol) of 5-tert-butyl 2-ethyl 3-[1-(ethyldimethylsilyl)cyclobutanecarboxamido]-6,6-dimethylpyrrolo[3,4-c]pyrazole-2,5(4H,6H)-dicarboxylate synthesized in the similar manner as in Reference Example 11 in 200 ml of dehydrated dichloromethane, 7.3 ml (43 mmol) of DIPEA was added at room temperature in an argon atmosphere, and then, a solution of 3.24 g (10.9 mmol) of bis(trichloromethyl)carbonate in 33 ml of dehydrated dichloromethane was added dropwise at −60° C. or lower and stirred at the same temperature as above for 2 hours.

After the completion of the reaction, 130 ml of a saturated aqueous solution of sodium bicarbonate was added to the reaction solution, and the temperature was raised to room temperature for a while with stirring. After separation into an aqueous layer and an organic layer, the aqueous layer was subjected to extraction with 100 ml of dichloromethane twice. All of the obtained organic layers were dried over anhydrous magnesium sulfate and filtered, and the filtrate was concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (elution solvent: n-hexane:ethyl acetate=78:22 to 57:43 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. n-Hexane was added to the concentration residue and concentrated again under reduced pressure to obtain 5.13 g of the title compound (yield: 76% [2 steps]) as a white solid.

Mass spectrum (CI, m/z): 455 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 9.85-9.76 (m, 1H), 4.88-4.81 & 4.53-4.48 (m, total 2H), 4.44 (q, J=7.1 Hz, 2H), 2.55-2.44 (m, 2H), 2.35-2.24 (m, 2H), 1.96-1.85 (m, 2H), 1.69-1.61 (m, 6H), 1.34 (t, J=7.1 Hz, 3H), 0.92 (t, J=7.9 Hz, 3H), 0.58 (q, J=7.9 Hz, 2H), 0.13-0.07 (m, 6H).

Reference Example 14

2-(Ethyldimethylsilyl)-2-methylpropanoic acid

To 100 ml of dehydrated THF, 100 ml (200 mmol) of 2 M lithium diisopropylamide/THF solution was added in an argon atmosphere, and then, 4.7 ml (51 mmol) of isobutanoic acid was added dropwise at 0° C. and stirred for 4 hours after the temperature was raised to room temperature. Subsequently, 10 ml (58 mmol) of hexamethylphosphoric acid triamide was added thereto, and then, 32 ml (230 mmol) of chloro(ethyl)dimethylsilane was added thereto dropwise at −78° C. After the completion of the dropwise addition, the resultant was stirred for 1 day while the temperature was raised to room temperature for a while.

After the completion of the reaction, 25 ml of methanol and subsequently 50 ml of water were added under cooling in ice water. Then, 2 N hydrochloric acid was added for acidity, followed by extraction with diethyl ether. The obtained organic layer was washed with a saturated aqueous solution of sodium chloride, then dried over anhydrous magnesium sulfate, and filtered, and the filtrate was concentrated under reduced pressure. A 2 N aqueous sodium hydroxide solution was added to the concentration residue, and it was washed with ethyl acetate. Subsequently, the aqueous layer was rendered acidic by adding a 1 N aqueous hydrochloric acid solution, followed by extraction with ethyl acetate. The obtained organic layer was dried over anhydrous magnesium sulfate and filtered, and the filtrate was concentrated under reduced pressure. The obtained residue was subjected to silica gel column chromatography (elution solvent: 1,2-dichloroethane:methanol=100:0 to 99:1 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure and dried under reduced pressure to obtain 2.24 g of the title compound (yield: 25%) as a white solid.

Mass spectrum (CI, m/z): 175 [M+1] + .

1 H-NMR spectrum (400 MHz, CDCl 3 ) δ: 11.57 (br s, 1H), 1.23 (s, 6H), 0.95 (t, J=8.0 Hz, 3H), 0.62 (q, J=8.0 Hz, 2H), 0.06 (s, 6H).

Reference Example 15

5-tert-Butyl 1-ethyl 3-[2-(ethyldimethylsilyl)-2-methylpropanamido]-6,6-dimethylpyrrolo[3,4-c]pyrazole-1,5(4H,6H)-dicarboxylate

To a solution of 4.7 g (27 mmol) of 2-(ethyldimethylsilyl)-2-methylpropanoic acid synthesized in the similar manner as in Reference Example 14 in 40 ml of dehydrated dichloromethane, 2.3 ml (27 mmol) of oxalyl chloride was added dropwise at 0° C. in an argon atmosphere and stirred at the same temperature as above for 10 minutes. Subsequently, 0.10 ml (1.3 mmol) of DMF was added at 0° C. and stirred at the same temperature as above for 4 hours.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure at room temperature to obtain a concentration residue.

To a solution of 2.9 g (8.9 mmol) of 5-tert-butyl 1-ethyl 3-amino-6,6-dimethylpyrrolo[3,4-c]pyrazole-1,5(4H,6H)-dicarboxylate [synthesized according to the method described in Journal of Medicinal Chemistry 2012, 55 (10), 4728-4739] in 10 ml of dehydrated dichloromethane, a solution of the obtained concentration residue in 20 ml of dehydrated dichloromethane was added dropwise at 0° C. in an argon atmosphere, and subsequently, 7.9 ml (45 mmol) of DIPEA was added and stirred at 0° C. for 24 hours.

After the completion of the reaction, water was added to the reaction solution, followed by extraction with dichloromethane. The obtained organic layer was washed with a saturated aqueous solution of sodium chloride, then dried over anhydrous sodium sulfate, and filtered, and the filtrate was concentrated under reduced pressure. The obtained residue was subjected to silica gel column chromatography (elution solvent: n-hexane:ethyl acetate=98:2 to 80:20 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure to obtain 3.18 g of the title compound (yield: 74%) as a pale yellow oil.

Mass spectrum (CI, m/z): 481 [M+1] + .

1 H-NMR spectrum (400 MHz, CDCl 3 ) δ: 7.88-7.73 (m, 1H), 4.62-4.46 (m, 4H), 1.87-1.75 (m, 6H), 1.55-1.41 (m, 12H), 1.31-1.26 (m, 6H), 0.99-0.88 (m, 3H), 0.66-0.53 (m, 2H), 0.09-0.02 (m, 6H).

Reference Example 16

Ethyl 3-[2-(ethyldimethylsilyl)-2-methylpropanamido]-6,6-dimethyl-5,6-dihydropyrrolo[3,4-c]pyrazole-1 (4H)-carboxylate

To a solution of 3.18 g (6.62 mmol) of 5-tert-butyl 1-ethyl 3-[2-(ethyldimethylsilyl)-2-methylpropanamido]-6,6-dimethylpyrrolo[3,4-c]pyrazole-1,5(4H,6H)-dicarboxylate synthesized in the similar manner as in Reference Example 15 in 30 ml of dehydrated dichloromethane, 2.3 ml (20 mmol) of 2,6-lutidine and 3.6 ml (20 mmol) of trimethylsilyl trifluoromethanesulfonate were added dropwise in this order at 0° C. in an argon atmosphere and stirred at the same temperature as above for 1 hour.

After the completion of the reaction, a saturated aqueous solution of sodium bicarbonate was added to the reaction solution, followed by extraction with dichloromethane. The obtained organic layer was washed with a saturated aqueous solution of sodium chloride, then dried over anhydrous magnesium sulfate, and filtered, and the filtrate was concentrated under reduced pressure. Toluene was added to the residue, and then, concentration under reduced pressure was performed to obtain 2.44 g of the title compound (yield: 97%) as a pale yellow solid.

Mass spectrum (CI, m/z): 381 [M+1] + .

1 H-NMR spectrum (400 MHz, CDCl 3 ) δ: 7.77 (s, 1H), 4.50 (q, J=7.2 Hz, 2H), 4.15 (s, 2H), 1.55 (s, 6H), 1.46 (t, J=7.2 Hz, 3H), 1.32-1.25 (m, 6H), 0.93 (t, J=8.0 Hz, 3H), 0.60 (q, J=8.0 Hz, 2H), 0.05 (s, 6H).

Reference Example 17

(S)-2-[(2-Methoxypropan-2-yl)oxy]-1-phenylethanol

To a solution of 664 mg (2.63 mmol) of (S)-2-[(tert-butyldimethylsilyl)oxy]-2-phenylethanol [synthesized according to the method described in Angew. Chem. Int. Ed., 2012, 51 (31), 7825-7829] in 15 ml of dichloromethane, 0.33 ml (3.5 mmol) of 2-methoxy-1-propene and 68.3 mg (0.272 mmol) of pyridinium p-toluenesulfonate were added at 0° C. in a nitrogen atmosphere and stirred at the same temperature as above for 2 hours.

After the completion of the reaction, a saturated aqueous solution of sodium bicarbonate was added to the reaction solution and stirred, followed by extraction with dichloromethane twice. All of the organic layers were dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (elution solvent: n-hexane:ethyl acetate=98:2 to 97:3 (V/V)), and a fraction containing (S)-3,3,8,8,9,9-hexamethyl-6-phenyl-2,4,7-trioxa-8-siladecane was concentrated under reduced pressure and dried under reduced pressure to obtain a concentration residue.

To a solution of 347 mg of the obtained concentration residue in 10 ml of THF, 428 mg (1.64 mmol) of tetrabutylammonium fluoride was added at 0° C. in a nitrogen atmosphere and stirred at the same temperature as above for 3.5 hours.

After the completion of the reaction, a saturated aqueous solution of sodium bicarbonate was added to the reaction solution and stirred, followed by extraction with an ethyl acetate/n-hexane mixed solvent twice. All of the obtained organic layers were dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (elution solvent: n-hexane:ethyl acetate=90:10 to 85:15 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure and dried under reduced pressure to obtain 160 mg of the title compound (yield: 29% [2 steps]) as a colorless oil.

1 H-NMR spectrum (400 MHz, CDCl 3 ) δ: 7.43-7.27 (m, 5H), 4.89-4.83 (m, 1H), 3.59 (dd, J=3.2, 9.8 Hz, 1H), 3.45 (dd, J=9.0, 9.8 Hz, 1H), 3.19 (s, 3H), 2.82 (d, J=2.4 Hz, 1H), 1.38 (s, 3H), 1.37 (s, 3H).

Reference Example 18

(S)-2,5-Dioxopyrrolidin-1-yl {2-[(2-methoxypropan-2-yl)oxy]-1-phenylethyl}carbonate

To a solution of 157 mg (0.747 mmol) of (S)-2-[(2-methoxypropan-2-yl)oxy]-1-phenylethanol synthesized in the similar manner as in Reference Example 17 in 4 ml of dehydrated acetonitrile, 0.16 ml (1.2 mmol) of triethylamine and 233 mg (0.908 mmol) of N,N′-disuccinimidyl carbonate were added at room temperature in a nitrogen atmosphere and stirred at the same temperature as above for 6 hours.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure. The obtained concentration residue was dissolved in ethyl acetate, and it was washed with water. After separation into an aqueous layer and an organic layer, the aqueous layer was subjected to extraction with ethyl acetate twice. All of the obtained organic layers were dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel column chromatography (elution solvent: n-hexane:ethyl acetate=90:10 to 65:35 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure and dried under reduced pressure to obtain 190 mg of the title compound (yield: 72%) as a colorless oil.

1 H-NMR spectrum (400 MHz, CDCl 3 ) δ: 7.42-7.33 (m, 5H), 5.86 (dd, J=3.4, 8.8 Hz, 1H), 3.83 (dd, J=8.8, 11.0 Hz, 1H), 3.64 (dd, J=3.4, 11.0 Hz, 1H), 3.20 (s, 3H), 2.81 (s, 4H), 1.38 (s, 3H), 1.34 (s, 3H).

Reference Example 19

Ethyl 4-(benzyloxy)-3-phenylbutanoate

To a solution of 8.9 mg (0.023 mmol) of bis(acetonitrile)(1,5-cyclooctadiene)rhodium(I) tetrafluoroborate in 3 ml of 1,4-dioxane/0.3 ml of water, 23 mg (0.41 mmol) of potassium hydroxide, 128 mg (1.05 mmol) of phenylboronic acid, and 120 mg (0.545 mmol) of (E)-ethyl 4-(benzyloxy)-2-butenoate [synthesized according to the method described in Tetrahedron Lett., 1982, 37, 9033-9036] were added in this order with stirring at room temperature in an argon atmosphere, stirred at the same temperature as above for 30 minutes, and then stirred at 60° C. for 6 hours.

After the completion of the reaction, water was added to the reaction solution, followed by extraction with ethyl acetate. The obtained organic layer was washed with a saturated aqueous solution of sodium chloride, then dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The obtained residue was subjected to silica gel chromatography (elution solvent: n-hexane:ethyl acetate=95:5 to 50:50 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure to obtain 160 mg of the title compound (yield: 98%) as a pale yellow oil.

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 7.36-7.18 (m, 10H), 4.45 (s, 2H), 3.97-3.89 (m, 2H), 3.59-3.52 (m, 2H), 3.39-3.33 (m, 1H), 2.81 (dd, J=6.3, 15.6 Hz, 1H), 2.59 (dd, J=8.5, 15.6 Hz, 1H), 1.04 (t, J=7.1 Hz, 3H).

Reference Example 20

Ethyl 6,6-dimethyl-5-(3-oxo-3-phenylpropanoyl)-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate and (Z)-ethyl 5-(3-hydroxy-3-phenylacryloyl)-6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate as tautomer

To a solution of 487 mg (2.39 mmol) of 3-oxo-3-phenylpropanoic acid [synthesized according to the method described in Chem. Pharm. Bull., 29 (10), 2762 (1981)] and 10 μl (0.13 mmol) of DMF in 5 ml of dehydrated dichloromethane, 205 μl (2.39 mmol) of oxalyl chloride was added dropwise with stirring at 0° C. in an argon atmosphere and stirred for 1.5 hours after the temperature was raised to room temperature.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure at room temperature to obtain a concentration residue.

To a solution of 299 mg (0.790 mmol) of ethyl 6,6-dimethyl-3-[1-(trimethylsilyl)cyclobutanecarboxamido]-5,6-dihydropyrrolo[3,4-c]pyrazole-2(4H)-carboxylate synthesized in the similar manner as in Reference Example 84 and 0.70 ml (4.1 mmol) of DIPEA in 5 ml of 1,2-dichloroethane, a solution of the obtained concentration residue in 5 ml of 1,2-dichloroethane was added dropwise with stirring at room temperature in an argon atmosphere and stirred at the same temperature as above for 5 hours.

After the completion of the reaction, 5 ml of 2-propanol was added and stirred at room temperature for 14 hours, and then, the reaction solution was concentrated under reduced pressure. The obtained residue was subjected to silica gel column chromatography (elution solvent: n-hexane:ethyl acetate=87:13 to 0:100 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure to obtain 293 mg of the title compound (yield: 71%) (containing the tautomer) as a pale yellow solid.

Mass spectrum (DUIS, m/z): 525 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 15.71 (s, 0.3H), 9.79 (s, 0.3H), 9.75 (s, 0.7H), 8.01-7.42 (m, total 5H), 5.82 (s, 0.3H), 4.85 (s, 0.6H), 4.78 (s, 1.4H), 4.47-4.38 (m, total 2H), 4.18 (s, 1.4H), 2.57-2.41 (m, total 2H), 2.33-2.12 (m, total 2H), 1.93-1.81 (m, total 2H), 1.75 & 1.64 (s, total 6H), 1.38-1.31 (m, total 3H), 0.11 & 0.08 (s, total 9H).

Reference Example 21

(R)-Methyl 3-amino-3-phenylpropanoate hydrochloride

To a solution of 2.01 g (12.2 mmol) of (R)-3-amino-3-phenylpropanoic acid [purchased from Shanghai HC Biotech Co., Ltd.] in 100 ml of dehydrated methanol, 1.32 ml (18.2 mmol) of thionyl chloride was added dropwise with stirring at room temperature in a nitrogen atmosphere and then stirred at the same temperature as above for 24 hours. Then, the temperature was raised to 65° C., and the resultant was stirred for 9.5 hours.

After standing to cool, the reaction solution was concentrated under reduced pressure, diethyl ether was added to the obtained concentration residue and ultrasonicated, and the deposited solid was collected by filtration and dried under reduced pressure to obtain 2.55 g of the title compound (yield: 97%) as a white solid.

Mass spectrum (DUIS, m/z): 180 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 8.67 (br s, 3H), 7.57-7.50 (m, 2H), 7.45-7.36 (m, 3H), 4.58 (dd, J=6.0, 8.6 Hz, 1H), 3.35 (br s, 3H), 3.20 (dd, J=6.0, 16.3 Hz, 1H), 3.00 (dd, J=8.6, 16.3 Hz, 1H).

Reference Example 22

(R)-Methyl 3-phenyl-3-(2,2,2-trifluoroacetamido)propanoate

To a solution of 2.55 g (11.8 mmol) of (R)-methyl 3-amino-3-phenylpropanoate hydrochloride synthesized in the similar manner as in Reference Example 21 in 50 ml of dichloromethane, 10.5 ml (60.3 mmol) of DIPEA and 1.75 ml (12.4 mmol) of trifluoroacetic anhydride were added dropwise in this order with stirring at 0° C. in an argon atmosphere, stirred at the same temperature as above for 2 hours, and further stirred overnight at room temperature.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure. Ethyl acetate was added to the concentration residue, washed with a saturated aqueous solution of sodium bicarbonate and a saturated aqueous solution of sodium chloride in this order, then dried over anhydrous magnesium sulfate, and filtered, and the filtrate was concentrated under reduced pressure. The obtained residue was subjected to silica gel column chromatography (elution solvent: n-hexane:ethyl acetate=91:9 to 70:30 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure to obtain 2.75 g of the title compound (yield: 85%) as a white solid.

Mass spectrum (DUIS, m/z): 276 [M+1] + .

1 H-NMR spectrum (400 MHz, CDCl 3 ) δ: 7.80-7.64 (m, 1H), 7.39-7.25 (m, 5H), 5.46-5.39 (m, 1H), 3.65 (s, 3H), 3.00 (dd, J=5.5, 16.2 Hz, 1H), 2.93 (dd, J=5.5, 16.2 Hz, 1H).

Reference Example 23

(R)-4-Amino-2-methyl-4-phenylbutan-2-ol

To a solution of 506 mg (1.84 mmol) of (R)-methyl 3-phenyl-3-(2,2,2-trifluoroacetamido)propanoate synthesized in the similar manner as in Reference Example 22 in 5 ml of dehydrated THF, 6.60 ml (9.24 mmol) of 1.4 M methyl magnesium bromide/THF solution was added dropwise with stirring at room temperature in an argon atmosphere and stirred at room temperature for 3.5 hours.

After the completion of the reaction, 10 ml of a saturated aqueous solution of ammonium chloride was added dropwise to the reaction solution under ice cooling, brought back to room temperature, and stirred for a while. Dichloromethane and water, and further an aqueous solution of dilute sodium hydroxide were added to the reaction solution to adjust the pH of the aqueous layer to 10, followed by separation into an aqueous layer and an organic layer. The aqueous layer was subjected to extraction with dichloromethane, all of the obtained organic layers were dried over anhydrous sodium sulfate and filtered, and the filtrate was concentrated under reduced pressure. The obtained residue was subjected to silica gel column chromatography (DNH silica gel, elution solvent: 1,2-dichloroethane:methanol=100:0 to 95:5 (V/V)), and a fraction containing (R)-2,2,2-trifluoro-N-(3-hydroxy-3-methyl-1-phenylbutyl)acetamide was concentrated under reduced pressure to obtain a concentration residue.

To a solution of 427 mg of the obtained concentration residue in 5 ml of ethanol, 64.6 mg (1.71 mmol) of sodium borohydride was added in several divided portions at room temperature and then stirred at room temperature for 14 hours. 77.0 mg (2.04 mmol) of sodium borohydride was further added in several divided portions, stirred at room temperature for 2 hours, and then stirred at 75° C. for 2 hours.

After the completion of the reaction, the reaction solution was cooled in ice, and 10 ml of a saturated aqueous solution of ammonium chloride was added thereto dropwise and then stirred at room temperature. Dichloromethane and water were added thereto, and an aqueous solution of dilute sodium hydroxide was added thereto to adjust the pH of the aqueous layer to 10, followed by separation into an aqueous layer and an organic layer. The aqueous layer was subjected to extraction with dichloromethane, all of the obtained organic layers were dried over anhydrous sodium sulfate and filtered, and the filtrate was concentrated under reduced pressure. The concentration residue was subjected to silica gel column chromatography (DNH silica gel, elution solvent: 1,2-dichloroethane:methanol=100:0 to 95:5 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure to obtain 160 mg of the title compound (yield: 49%) as a colorless oil.

Mass spectrum (DUIS, m/z): 180 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 7.37-7.26 (m, 4H), 7.21-7.15 (m, 1H), 4.05 (dd, J=2.8, 10.7 Hz, 1H), 1.66 (dd, J=10.7, 14.0 Hz, 1H), 1.52 (dd, J=2.8, 14.0 Hz, 1H), 1.22 (s, 3H), 1.10 (s, 3H).

Reference Example 24

(S)-tert-Butyl [2-(difluoromethoxy)-1-phenylethyl]carbamate

To a solution of 1.00 g (4.21 mmol) of (S)-tert-butyl (2-hydroxy-1-phenylethyl)carbamate [purchased from Novo Chemy Ltd.] in 30 ml of dehydrated acetonitrile, 165 mg (0.866 mmol) of copper(I) iodide was added at room temperature in an argon atmosphere and stirred at the same temperature as above for 30 minutes. Subsequently, a solution of 0.87 ml (8.4 mmol) of 2-(fluorosulfonyl)difluoroacetic acid in 10 ml of dehydrated acetonitrile was dividedly added (1 ml each) at 45° C. over 40 minutes and stirred at the same temperature as above for 1 hour.

After the completion of the reaction, the reaction solution allowed to cool to room temperature was concentrated under reduced pressure. Water and ethyl acetate were added to the obtained concentration residue, followed by extraction from the mixed solution with ethyl acetate. The obtained organic layer was washed with water, then dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The obtained concentration residue was subjected to silica gel chromatography (elution solvent: n-hexane:ethyl acetate=95:5 to 50:50 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained concentration residue was subjected again to silica gel chromatography (elution solvent: n-hexane:ethyl acetate=95:5 to 50:50 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure and dried under reduced pressure to obtain 213 mg of the title compound (yield: 18%) as a yellow solid.

Mass spectrum (CI, m/z): 288 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 7.55 (d, J=8.7 Hz, 1H), 7.37-7.24 (m, 5H), 6.67 (t, J=75.9 Hz, 1H), 4.83-4.73 (m, 1H), 3.95-3.86 (m, 2H), 1.42-1.23 (m, 9H).

Reference Example 25

(S)-2-(Difluoromethoxy)-1-phenylethanamine trifluoroacetate

To a solution of 210 mg (0.731 mmol) of (S)-tert-butyl [2-(difluoromethoxy)-1-phenylethyl]carbamate synthesized in the similar manner as in Reference Example 24 in 4 ml of dehydrated dichloromethane, 1 ml of trifluoroacetic acid was added at room temperature in an argon atmosphere and stirred at the same temperature as above for 2 hours.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure and dried under reduced pressure to obtain 210 mg of the title compound (yield: 95%) as a yellow oil.

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 8.59 (br s, 3H), 7.54-7.40 (m, 5H), 6.76 (t, J=74.8 Hz, 1H), 4.70-4.59 (m, 1H), 4.19-4.11 (m, 2H).

Reference Example 26

(S)-2-Ethoxy-1-phenylethanamine

To a solution of 1.40 g (10.2 mmol) of (S)-2-amino-2-phenylethanol and 3.0 ml (15 mmol) of 1,4,7,10,13-pentaoxacyclopentadecane in 10 ml of dehydrated THF, 481 mg (11.0 mmol) of 55% sodium hydride was dividedly added with stirring at room temperature in an argon atmosphere and stirred at the same temperature as above until foaming settled. Subsequently, 0.82 ml (10 mmol) of ethyl iodide was added dropwise at room temperature and stirred at the same temperature as above for 24 hours.

After the completion of the reaction, water and diethyl ether were added to the reaction solution and then the aqueous layer and the organic layer were separated. The aqueous layer was subjected to extraction with diethyl ether, then all of the organic layers were washed with a saturated aqueous solution of sodium chloride, dried over anhydrous sodium sulfate, and filtered, and the filtrate was concentrated under reduced pressure. The obtained residue was subjected to silica gel column chromatography (DNH silica gel, elution solvent: 1,2-dichloroethane:methanol=100:0 to 95:5 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure to obtain 1.17 g of the title compound (yield: 69%) as a pale yellow oil.

Mass spectrum (CI, m/z): 166 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 7.39-7.33 (m, 2H), 7.33-7.25 (m, 2H), 7.25-7.19 (m, 1H), 4.01 (dd, J=4.9, 8.0 Hz, 1H), 3.53-3.35 (m, 3H), 3.28 (dd, J=8.0, 9.3 Hz, 1H), 1.82 (br s, 2H), 1.09 (t, J=7.0 Hz, 3H).

Reference Example 27

(R)-3-Methoxy-1-phenylpropan-1-amine

To a solution of 1.53 g (10.1 mmol) of (R)-3-amino-3-phenylpropan-1-ol [purchased from Ark Pharm, Inc.] and 3.0 ml (15 mmol) of 1,4,7,10,13-pentaoxacyclopentadecane in 10 ml of dehydrated THF, 473 mg (10.9 mmol) of 55% sodium hydride was dividedly added with stirring at room temperature in an argon atmosphere and stirred at the same temperature as above until foaming settled. Subsequently, 0.62 ml (10 mmol) of methyl iodide was added thereto dropwise at 0° C. and then stirred at room temperature for 17 hours.

After the completion of the reaction, water and diethyl ether were added to the reaction solution and then the aqueous layer and the organic layer were separated. The aqueous layer was subjected to extraction with diethyl ether, then all of the organic layers were washed with a saturated aqueous solution of sodium chloride, dried over anhydrous sodium sulfate, and filtered, and the filtrate was concentrated under reduced pressure. The obtained residue was subjected to silica gel column chromatography (DNH silica gel, elution solvent: 1,2-dichloroethane:methanol=100:0 to 95:5 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure to obtain 1.49 g of the title compound (yield: 89%) as a colorless oil.

Mass spectrum (CI, m/z): 166 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 7.35-7.26 (m, 4H), 7.24-7.15 (m, 1H), 3.85 (dd, J=6.4, 7.4 Hz, 1H), 3.38-3.20 (m, 2H), 3.19 (s, 3H), 1.93-1.63 (m, 4H).

Reference Example 28

2-(Benzo[d][1,3]dioxol-4-yl)-2-[(tert-butoxycarbonyl)amino]acetic acid

To a solution of 7.09 g (47.2 mmol) of benzo[d][1,3]dioxole-4-carbaldehyde in 15 ml of methanol, 67.5 ml (472 mmol) of 7 M aqueous ammonia solution/methanol solution was gradually added at room temperature and then stirred at room temperature for 18 minutes. The reaction solution was cooled in ice water, and 14.1 ml (113 mmol) of trimethylsilane carbonitrile was added dropwise. After the completion of the dropwise addition, the resultant was stirred overnight at room temperature.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure to obtain a concentration residue.

To 9.30 g of the obtained concentration residue, 17 ml of acetic acid and 66.7 ml (776 mmol) of concentrated hydrochloric acid were added and stirred for 9 hours while heated to reflux.

After standing to cool, the reaction solution was concentrated under reduced pressure to obtain a concentration residue.

To 8.33 g of the obtained concentration residue, 35.2 ml (141 mmol) of a 4 N aqueous sodium hydroxide solution, 65 ml of 1,4-dioxane, and 14.7 ml (64.1 mmol) of di-tert-butyl dicarbonate were added in this order at room temperature and stirred at room temperature.

After the completion of the reaction, the reaction solution was concentrated under reduced pressure, 100 ml of dichloromethane was added thereto, and then, the pH was adjusted to 1.75 by using concentrated hydrochloric acid. Methanol was added thereto until insoluble matter was dissolved, and then the aqueous layer and the organic layer were separated. The aqueous layer was subjected to extraction with 100 ml of dichloromethane twice, all of the obtained organic layers were dried over anhydrous magnesium sulfate and filtered, and the filtrate was concentrated under reduced pressure. The obtained residue was subjected to silica gel column chromatography (elution solvent: ethyl acetate), and a fraction containing the compound of interest was concentrated under reduced pressure. The obtained residue was subjected again to silica gel column chromatography (elution solvent: ethyl acetate), and a fraction containing the compound of interest was concentrated under reduced pressure to obtain 10.22 g of the title compound (yield: 73% [3 steps]) as a black viscous liquid.

Mass spectrum (DUIS, m/z): 296 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 13.24-12.32 (m, 1H), 7.48 (d, J=8.5 Hz, 1H), 6.88-6.77 (m, 3H), 6.04-6.01 (m, 2H), 5.22 (d, J=8.5 Hz, 1H), 1.38 (s, 9H).

Reference Example 29

Methyl 2-(benzo[d][1,31]dioxol-4-yl)-2-[(tert-butoxycarbonyl)amino]acetate

To a solution of 3.93 g (13.3 mmol) of 2-(benzo[d][1,3]dioxol-4-yl)-2-[(tert-butoxycarbonyl)amino]acetic acid synthesized in the similar manner as in Reference Example 28 in 8 ml of DMF, 3.86 g (27.9 mmol) of potassium carbonate and 1.3 ml (21 mmol) of methyl iodide were added in this order at room temperature, stirred at the same temperature as above for 1 hour, and then left standing overnight.

After the completion of the reaction, the reaction solution was poured to 100 ml of a saturated aqueous solution of sodium chloride, and water was added until insoluble matter was dissolved, followed by extraction with toluene twice. The obtained organic layer was dried over anhydrous sodium sulfate and filtered, and then, the filtrate was concentrated under reduced pressure. The obtained residue was subjected to silica gel column chromatography (elution solvent: hexane:ethyl acetate=95:5 to 70:30 (V/V)), and a fraction containing the compound of interest was concentrated under reduced pressure to obtain 2.83 g of the title compound (yield: 69%) as a white solid.

Mass spectrum (EI, m/z): 309 [M] + .

1 H-NMR spectrum (400 MHz, CDCl 3 ) δ: 6.85-6.76 (m, 3H), 6.03-5.97 (m, 2H), 5.71-5.61 (m, 1H), 5.49-5.39 (m, 1H), 3.73 (s, 3H), 1.47-1.39 (m, 9H).

Reference Example 30

tert-Butyl [1-(benzo[d][1,3]dioxol-4-yl)-2-hydroxyethyl]carbamate

To a solution of 2.82 g (9.13 mmol) of methyl 2-(benzo[d][1,3]dioxol-4-yl)-2-[(tert-butoxycarbonyl)amino]acetate synthesized in the similar manner as in Reference Example 29 in 30 ml of dehydrated THF, 716 mg (32.9 mmol) of lithium borohydride was added under cooling in ice water and stirred at room temperature.

After the completion of the reaction, the reaction solution was poured to 150 ml of a saturated aqueous solution of ammonium chloride, followed by extraction with ethyl acetate. The obtained organic layer was dried over anhydrous magnesium sulfate and filtered, and the filtrate was concentrated under reduced pressure. Diethyl ether and n-hexane were added to the concentration residue, and the formed solid was filtered, washed by sousing with diethyl ether, and then dried under reduced pressure to obtain 1.54 g of the title compound (yield: 60%) as a white solid.

Mass spectrum (CI, m/z): 282 [M+1] + .

1 H-NMR spectrum (400 MHz, DMSO-d 6 ) δ: 7.13 (d, J=8.3 Hz, 1H), 6.84-6.75 (m, 3H), 6.02-5.96 (m, 2H), 4.82 (t, J=5.6 Hz, 1H), 4.74-4.64 (m, 1H), 3.54-3.40 (m, 2H), 1.37 (s, 9H).

Reference Example 31

2-Amino-2-(benzo[d][1,3]dioxol-4-yl)ethanol

To a solution of 1.04 g (3.69 mmol) of tert-butyl [1-(benzo[d][1,3]dioxol-4-yl)-2-hydroxy