Cl.[Cl:2][C:3]1[CH:4]=[C:5]([NH:11][C@H:12]([CH2:17][NH:18][CH:19]([CH3:21])[CH3:20])[CH2:13][C:14](O)=[O:15])[CH:6]=[CH:7][C:8]=1[C:9]#[N:10].C[Si](N[Si](C)(C)C)(C)C>CC#N.O>[Cl:2][C:3]1[CH:4]=[C:5]([NH:11][C@H:12]2[CH2:13][C:14](=[O:15])[N:18]([CH:19]([CH3:21])[CH3:20])[CH2:17]2)[CH:6]=[CH:7][C:8]=1[C:9]#[N:10]The crude (3S)-3-[(3-chloro-4-cyanophenyl)amino]-4-[(1-methylethyl)amino]butanoic acid hydrochloride was dissolved in MeCN (20 mL) and treated with HMDS (4 mL) and the reaction was stirred at 60° C. for 15 h. After cooled down, the reaction was diluted with H2O and extracted with Et2O (2×). The combined organic extracts were washed with H2O (2×), dried over Na2SO4, filtered, concentrated, and purified by silica gel chromatography with 25% EtOAC in hexane grading to 100% EtOAc in hexane to yield the titled product (0.13 g, 49%). LC-MS (ES) m/e 277.9 (M+H)+.
読み込み中…