[CH3:1][O:2][C:3](=[O:27])[CH2:4][CH2:5][CH2:6][CH2:7][CH2:8][CH2:9][N:10]1[C:14](=[O:15])[CH2:13][CH2:12][C@@H:11]1/[CH:16]=[CH:17]/[C:18]([C:20]1[CH:25]=[CH:24][CH:23]=[C:22]([Br:26])[CH:21]=1)=[O:19].[BH4-].[Na+].Cl>CO>[CH3:1][O:2][C:3](=[O:27])[CH2:4][CH2:5][CH2:6][CH2:7][CH2:8][CH2:9][N:10]1[C:14](=[O:15])[CH2:13][CH2:12][C@@H:11]1/[CH:16]=[CH:17]/[CH:18]([C:20]1[CH:25]=[CH:24][CH:23]=[C:22]([Br:26])[CH:21]=1)[OH:19]To a solution of 7-{(R)-2-[(E)-3-(3-bromo-phenyl)-3-oxo-propenyl]-5-oxo-pyrrolidin-1-yl}-heptanoic acid methyl ester (0.78 g, 1.79 mmol) in 15 mL of methanol stirred at 0° C. under nitrogen was added sodium borohydride (0.074 g). The reaction mixture was stirred at room temperature for 6 hours. After addition of 1 N HCl solution the mixture was extracted with ethyl acetate. The organic layer was dried over anhydrous magnesium sulfate, concentrated, and purified by chromatography eluting with 50% EtOAc and Hexane followed by 100% EtOAc to yield 670 mg of 7-{(R)-2-[(E)-3-(3-bromo-phenyl)-3-hydroxy-propenyl]-5-oxo-pyrrolidin-1-yl}-heptanoic acid methyl ester. Step 3
Wird geladen…