[CH2:1]([O:8][C:9]([NH:11][C:12]12[CH2:19][C:16]([C:20]([O-:22])=[O:21])([CH2:17][CH2:18]1)[CH2:15][CH2:14][CH2:13]2)=[O:10])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.[OH-].[Na+]>CO>[CH2:1]([O:8][C:9]([NH:11][C:12]12[CH2:19][C:16]([C:20]([OH:22])=[O:21])([CH2:17][CH2:18]1)[CH2:15][CH2:14][CH2:13]2)=[O:10])[C:2]1[CH:3]=[CH:4][CH:5]=[CH:6][CH:7]=1To a solution of 5-(benzyloxycarbonylamino)bicyclo-[3.2.1]octane-1-carboxylate (10 g, 31.5 mmol) in MeOH (150 mL) was added NaOH (2N, 50 mL) and the reaction solution was stirred at room temperature overnight. The organic solvent was removed under reduced pressure and the remaining aqueous solution was extracted with ethyl acetate (20 mL) to remove the organic impurities, and then adjusted to pH 3 with 2N aq. HCl. The acidic aqueous solution was extracted with ethyl acetate (3×20 mL) and the combined organic layer was washed with brine, dried over Na2SO4 and concentrated to give 9 g (95%) 5-(benzyloxycarbonylamino)bicyclo[3.2.1]octane-1-carboxylic acid as a colorless oil, which was solidified after standing at room temperature overnight. ESI-MS m/z: 304 (M+H)+.
Wird geladen…