[H-].[Na+].CN(C)C=O.[CH3:8][C:9]1[O:13][C:12]([C:14]2[CH:19]=[CH:18][CH:17]=[CH:16][CH:15]=2)=[N:11][C:10]=1[CH2:20][O:21][C:22]1[CH:42]=[CH:41][C:25]([CH2:26][N:27]2[C:39]3[CH:38]=[CH:37][CH:36]=[C:35]([OH:40])[C:34]=3[C:33]3[C:28]2=[CH:29][CH:30]=[CH:31][CH:32]=3)=[CH:24][C:23]=1[O:43][CH3:44].Br[C@H:46]([CH2:52][CH3:53])[C:47]([O:49][CH2:50][CH3:51])=[O:48]>O>[CH3:44][O:43][C:23]1[CH:24]=[C:25]([CH:41]=[CH:42][C:22]=1[O:21][CH2:20][C:10]1[N:11]=[C:12]([C:14]2[CH:15]=[CH:16][CH:17]=[CH:18][CH:19]=2)[O:13][C:9]=1[CH3:8])[CH2:26][N:27]1[C:39]2[CH:38]=[CH:37][CH:36]=[C:35]([O:40][C@@H:46]([CH2:52][CH3:53])[C:47]([O:49][CH2:50][CH3:51])=[O:48])[C:34]=2[C:33]2[C:28]1=[CH:29][CH:30]=[CH:31][CH:32]=241 mg of sodium hydride (60%) was added to N,N-dimethylformamide (2.5 mL) solution of 500 mg of 9-{4-[(5-methyl-2-phenyloxazole-4-yl)methoxy]-3-methoxybenzyl}-9H-carbazole-4-ol while being cooled in an ice bath, and stirred at room temperature for 1 hour. Thereafter, 239 mg of ethyl (R)-2-bromobutyrate was added thereto dropwise at −5° C., and was stirred for 30 minutes. Water was added to the reaction mixture, and extracted twice with ethyl acetate. The combined extract was washed with brine, and dried over anhydrous sodium sulfate. After filtration, the filtrate was concentrated in vacuo, the residue was purified by NH silica gel chromatography (ethyl acetate:n-hexane=1:4), and 650 mg of the subject compound was prepared. Optical purity 95% ee (HPLC).
Loading…