methyl (2R)-pyrrolidine-2-carboxylate;hydrochloride

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: The standard procedure was followed using N-(4-cyano-2-t-butyldimethylsilanoxyphenyl)-N′-(2-bromophenyl)carbodiimide (107 mg, 0.25 mmol), diisopropylethylamine (71 μL, 0.55 mmol), D-proline methyl ester hydro chloride (46 mg, 0.28 mmol) and TBAF (0.30 mL, 0.30 mmol) in THF (2.5 mL) and methanol (0.1 mL) to give 80 mg (78%) of 4-[[(7aR)-2-(2-bromophenyl)-hexahydro-1-oxo-3H-pyrrolo[1,2-c]imidazol-3-ylidene]amino]-3-hydroxybenzonitrile as a tan powder. MS(EI) m/e 411 (100(M+)).

Conditions: temp:25.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of 8-((R)-1-phenyl-propylcarbamoyI)-3,4-dihydro-1H-pyrrolo[2,1-c][1,4]oxazine-6-carboxylic acid (Comp. No. 11a) (200 mg, 0.61 mmol) in dimethylformamide (2 ml) was added 1-hydroxybenzotriazole (91 mg, 0.670 mmol) and 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (128 mg, 0.670 mmol). The mixture was stirred for 45 min at 25° C., then (R)-pyrrolidine-2-carboxylic acid methyl ester hydrochloride (111 mg, 0.670 mmol) and triethylamine (123 mg, 1.218 mmol) were added and the mixture was stirred at 25° C. overnight. Excess dichloromethane was added and the mixture was washed consecutively with water, aqueous sodium hydrogencarbonate and brine. The organic layer was evaporated to dryness. The crude product was purified by flash chromatography (silica gel, elution with heptane/ethyl acetate) to give 55 mg (21%) of (R)-1-[8-((R)-1-phenyl-propylcarbamoyI)-3,4-dihydro-1H-pyrrolo[2,1-c][1,4]oxazine-6-carbonyl]-pyrrolidine-2-carboxylic acid methyl ester). LC/MS (method 4): Rt=1.21 min; m/z=440.29 (M+H+). the mixture was stirred at 25° C. overnight the mixture was washed consecutively with water, aqueous sodium hydrogencarbonate and brine The organic layer was evaporated to dryness The crude product was purified by flash chromatography (silica gel, elution with heptane/ethyl acetate)

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: B21 was obtained as a white crystalline solid by following the procedure reported for B4 using A1 and (R)-proline methyl ester hydrochloride; yield: 158 mg (45%). 1H NMR (300 MHz, d6-DMSO, 300K) δ 1.88-2.08 (m, 3H), 2.22-2.42 (m, 1H), 3.50-3.77 (m, 2H), 3.55 and 3.60 (2 s, 3H), 4.22 (2 s, 2H), 4.50-4.67 (m, 1H), 6.88 (bs, 2H), 6.97-7.05 (m, 1H), 7.20-7.32 (m, 1H), 7.60-7.72 (m, 1H), 7.68 and 7.89 (2bs, 1H), 8.19 and 8.26 (2 s, 1H), 9.73 and 9.78 (2 s, 1H). MS (ES) C16H20N6O4S requires: 392. found: 393 (M+H)+. B21 was obtained as a white crystalline solid

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: The standard procedure was followed using N-(4-cyano-2-t-butyldimethylsilanoxyphenyl)-N′-(2-bromophenyl)carbodiimide (107 mg, 0.25 mmol), diisopropylethylamine (71 μL, 0.55 mmol), D-proline methyl ester hydro chloride (46 mg, 0.28 mmol) and TBAF (0.30 mL, 0.30 mmol) in THF (2.5 mL) and methanol (0.1 mL) to give 80 mg (78%) of 4-[[(7aR)-2-(2-bromophenyl)-hexahydro-1-oxo-3H-pyrrolo[1,2-c]imidazol-3-ylidene]amino]-3-hydroxybenzonitrile as a tan powder. MS(EI) m/e 411 (100(M+)).

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: H2O (0.0177 g, 0.131 mmol, 1.1 eq) was added to a stirred solution of 3-((2S,3R)-3-hydroxy-4-((5-isopropylpyridin-3-yl)methylamino)-1-phenylbutan-2-ylcarbamoyl)benzoic acid (0.055 g, 0.119 mmol, 1 eq) in 2 ml anhydrous CH2Cl2 at 0° C. under Ar. After 30 min EDCI.HCl (0.0197 g, 0.119 mmol, 1.1 eq) was added. After 30 min 1 ml anhydrous DMF was added. In a separate flask (R)-methylpyrrolidine-2-carboxylate hydrochloride (Bachem, 0.0197 g, 0.119 mmol, 1 eq) in 2 ml anhydrous CH2Cl2 under Ar was treated with DIPEA (0.083 ml, 0.062 g, 0.476 mmol, 4 eq). After both solutions had stirred for 1 h, the active ester was treated with the free-base amine. The reaction was stirred at 0° C. to room temperature overnight. The solvent was removed in vacuo. The residue was partitioned between EtOAc/H2O and the layers were separated. The organic layer was washed with water (×3), brine (×1), and dried over Na2SO4. The inorganics were filtered off, and the solvent removed in vacuo. Purification via flash chromatography yielded 0.0208 g (0.036 mmol, 31% yield) of (R)-methyl 1-(3-((2S,3R)-3-hydroxy-4-((5-isopropylpyridin-3-yl)methylamino)-1-phenylbutan-2-ylcarbamoyl)benzoyl)pyrrolidine-2-carboxylate, which was treated under hydrolysis conditions as described herein to generate (R)-1-(3-((2S,3R)-3-hydroxy-4-((5-isopropylpyridin-3-yl)methylamino)-1-phenylbutan-2-ylcarbamoyl)benzoyl)pyrrolidine-2-carboxylic acid. The reaction was stirred at 0° C. to room temperature overnight The solvent was removed in vacuo The residue was partitioned between EtOAc/H2O the layers were separated The organic layer was washed with water (×3), brine (×1) dried over Na2SO4 The inorganics were filtered off the solvent removed in vacuo Purification via flash chromatography

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 3.38 ml of triethylamine were added dropwise, over the course of 30 minutes, to a solution of 2.56 g of 3-nitrobenzenesulfonyl chloride and 1.91 g of methyl (R)-pyrrolidine-2-carboxylate hydrochloride in 30 ml of dichloromethane (30 ml) cooled to 0° C. The reaction medium was left at ambient temperature and stirred for 1 hour. The reaction medium was diluted with 50 ml of dichloromethane, and washed with a 1 M sodium hydrogen phosphate solution (2×50 ml) and a saturated sodium hydrogen carbonate solution (50 ml). The organic phase was dried over magnesium sulfate and evaporated 3.00 g of methyl (R)-1-(3-nitrobenzenesulfonyl)pyrrolidine-2-carboxylate were obtained and used in the next step without purification. The reaction medium was left at ambient temperature washed with a 1 M sodium hydrogen phosphate solution (2×50 ml) The organic phase was dried over magnesium sulfate evaporated 3.00 g of methyl (R)-1-(3-nitrobenzenesulfonyl)pyrrolidine-2-carboxylate were obtained used in the next step without purification

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A suspension of 5-bromo-3-bromomethyl-pyridin-2-ylamine hydrobromide (8.00 g, 23.1 mmol) and D-proline methyl ester hydrochloride (4.53 g, 27.4 mmol) in CH3CN (100 mL) was treated with a solution of triethylamine (10.4 mL, 74.0 mmol) in CH3CN (100 mL). After stirring at room temperature for 5 h, the cloudy mixture was diluted with H2O (300 mL) and extracted with EtOAc (3×200 mL). The combined organic layers were washed with brine (100 mL), dried over Na2SO4, filtered and the solvent was removed in vacuo. Purification by flash column chromatography (silica gel, CH2Cl2/MeOH, 99:1 to 98:2) gave the title compound (6.55 g, 90%) as a colorless oil: MS (ESI) m/e 314 (M+H)+ extracted with EtOAc (3×200 mL) The combined organic layers were washed with brine (100 mL) dried over Na2SO4 filtered the solvent was removed in vacuo Purification by flash column chromatography (silica gel, CH2Cl2/MeOH, 99:1 to 98:2)

Conditions: temp:25.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of 8-((R)-1-phenyl-propylcarbamoyI)-3,4-dihydro-1H-pyrrolo[2,1-c][1,4]oxazine-6-carboxylic acid (Comp. No. 11a) (200 mg, 0.61 mmol) in dimethylformamide (2 ml) was added 1-hydroxybenzotriazole (91 mg, 0.670 mmol) and 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (128 mg, 0.670 mmol). The mixture was stirred for 45 min at 25° C., then (R)-pyrrolidine-2-carboxylic acid methyl ester hydrochloride (111 mg, 0.670 mmol) and triethylamine (123 mg, 1.218 mmol) were added and the mixture was stirred at 25° C. overnight. Excess dichloromethane was added and the mixture was washed consecutively with water, aqueous sodium hydrogencarbonate and brine. The organic layer was evaporated to dryness. The crude product was purified by flash chromatography (silica gel, elution with heptane/ethyl acetate) to give 55 mg (21%) of (R)-1-[8-((R)-1-phenyl-propylcarbamoyI)-3,4-dihydro-1H-pyrrolo[2,1-c][1,4]oxazine-6-carbonyl]-pyrrolidine-2-carboxylic acid methyl ester). LC/MS (method 4): Rt=1.21 min; m/z=440.29 (M+H+). the mixture was stirred at 25° C. overnight the mixture was washed consecutively with water, aqueous sodium hydrogencarbonate and brine The organic layer was evaporated to dryness The crude product was purified by flash chromatography (silica gel, elution with heptane/ethyl acetate)

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: B21 was obtained as a white crystalline solid by following the procedure reported for B4 using A1 and (R)-proline methyl ester hydrochloride; yield: 158 mg (45%). 1H NMR (300 MHz, d6-DMSO, 300K) δ 1.88-2.08 (m, 3H), 2.22-2.42 (m, 1H), 3.50-3.77 (m, 2H), 3.55 and 3.60 (2 s, 3H), 4.22 (2 s, 2H), 4.50-4.67 (m, 1H), 6.88 (bs, 2H), 6.97-7.05 (m, 1H), 7.20-7.32 (m, 1H), 7.60-7.72 (m, 1H), 7.68 and 7.89 (2bs, 1H), 8.19 and 8.26 (2 s, 1H), 9.73 and 9.78 (2 s, 1H). MS (ES) C16H20N6O4S requires: 392. found: 393 (M+H)+. B21 was obtained as a white crystalline solid

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: The standard procedure was followed using N-(4-cyano-2-t-butyldimethylsilanoxyphenyl)-N′-(2-bromophenyl)carbodiimide (107 mg, 0.25 mmol), diisopropylethylamine (71 μL, 0.55 mmol), D-proline methyl ester hydro chloride (46 mg, 0.28 mmol) and TBAF (0.30 mL, 0.30 mmol) in THF (2.5 mL) and methanol (0.1 mL) to give 80 mg (78%) of 4-[[(7aR)-2-(2-bromophenyl)-hexahydro-1-oxo-3H-pyrrolo[1,2-c]imidazol-3-ylidene]amino]-3-hydroxybenzonitrile as a tan powder. MS(EI) m/e 411 (100(M+)).