[BH4-].[Na+].C(O)C.[Cl-].[Ca+2].[Cl-].[CH3:9][O:10][CH2:11][CH2:12][CH2:13][CH2:14][N:15]1[C:19]2[CH:20]=[CH:21][CH:22]=[CH:23][C:18]=2[N:17]=[C:16]1[C:24]([N:26]([CH2:44][CH:45]([CH3:47])[CH3:46])[C@@H:27]1[CH2:32][N:31]([C:33]([O:35][C:36]([CH3:39])([CH3:38])[CH3:37])=[O:34])[CH2:30][C@H:29]([C:40](OC)=[O:41])[CH2:28]1)=[O:25]>C1COCC1.O.C(OCC)(=O)C>[OH:41][CH2:40][C@@H:29]1[CH2:28][C@H:27]([N:26]([C:24]([C:16]2[N:15]([CH2:14][CH2:13][CH2:12][CH2:11][O:10][CH3:9])[C:19]3[CH:20]=[CH:21][CH:22]=[CH:23][C:18]=3[N:17]=2)=[O:25])[CH2:44][CH:45]([CH3:47])[CH3:46])[CH2:32][N:31]([C:33]([O:35][C:36]([CH3:38])([CH3:37])[CH3:39])=[O:34])[CH2:30]1Sodium borohydride (4.45 g) was suspended in THF (25 ml)-ethanol (75 ml), and calcium chloride (6.5 g) was added. After stirring at 0° C. for 1 hr, a solution of 1-tert-butyl 3-methyl (3R,5S)-5-[{[1-(4-methoxybutyl)-1H-benzimidazol-2-yl]carbonyl}(2-methylpropyl)amino]piperidine-1,3-dicarboxylate (4.0 g) in THF (50 ml) was added. After stirring at room temperature for 12 hr, ethyl acetate (150 ml) and water (50 ml) were slowly added in this order, and the mixture was filtered. The organic layer of the filtrate was partitioned, washed with brine, and dried over anhydrous sodium sulfate. The solvent was evaporated under reduced pressure. The residue was dried under reduced pressure to give the object product (1.8 g).
불러오는 중…