[C:1]([O:5][C:6](=[O:20])[NH:7][C:8]1([C:11]2[O:12][C:13]([C:16]([NH2:19])([CH3:18])[CH3:17])=[CH:14][CH:15]=2)[CH2:10][CH2:9]1)([CH3:4])([CH3:3])[CH3:2].Cl[C:22]([O:24][CH2:25][C:26]1[CH:31]=[CH:30][CH:29]=[CH:28][CH:27]=1)=[O:23]>C1COCC1.O>[C:1]([O:5][C:6](=[O:20])[NH:7][C:8]1([C:11]2[O:12][C:13]([C:16]([NH:19][C:22]([O:24][CH2:25][C:26]3[CH:31]=[CH:30][CH:29]=[CH:28][CH:27]=3)=[O:23])([CH3:18])[CH3:17])=[CH:14][CH:15]=2)[CH2:10][CH2:9]1)([CH3:4])([CH3:2])[CH3:3]To a solution of crude {1-[5-(1-amino-1-methyl-ethyl)-furan-2-yl]-cyclopropyl}-carbamic acid tert-butyl ester (451 mg, 1.61 mmol) in a mixture of THF (8.0 mL) and water (1.6 mL), was added Li2CO3 (297 mg, 4.02 mmol) followed by benzyl chloroformate (0.57 mL, 4.0 mmol). This was stirred for 2.5 h then diluted with water (50 mL) and extracted EtOAc (3×50 mL). The combined organic layers were dried with Na2SO4 and concentrated to give a red residue. The residue was purified by flash chromatography (silica, 20->40% EtOAc/hexanes) to give 324 mg of the title compound as a yellow oil, m/z 437.64 [M+Na]+.
読み込み中…