[C:1](#[N:3])[CH3:2].[Li]CCCC.[Cl:9][C:10]1[CH:15]=[CH:14][C:13]([C:16]([N:22]2[C:30]3[C:25](=[C:26]([NH:31][S:32]([CH3:35])(=[O:34])=[O:33])[CH:27]=[CH:28][CH:29]=3)[CH:24]=[CH:23]2)([CH2:20][CH3:21])[C:17](=[O:19])[CH3:18])=[CH:12][CH:11]=1>C1COCC1>[Cl:9][C:10]1[CH:15]=[CH:14][C:13]([C:16]([N:22]2[C:30]3[C:25](=[C:26]([NH:31][S:32]([CH3:35])(=[O:33])=[O:34])[CH:27]=[CH:28][CH:29]=3)[CH:24]=[CH:23]2)([CH2:20][CH3:21])[C:17]([OH:19])([CH3:18])[CH2:2][C:1]#[N:3])=[CH:12][CH:11]=1To a solution of acetonitrile (244 mg, 5.94 mmol) in THF (20 mL) was added n-BuLi (2.6 mL, 6.5 mmol, 2.5 M in hexane) dropwise at −78° C. After stirring for 0.5 h, a solution of the product from Step A (480 mg, 1.19 mmol) in THF (5 mL) was added to the mixture at −78° C. The resulting mixture was stirred at −78° C. for 0.5 h, and then quenched with saturated ammonium chloride solution, extracted with ethyl acetate. The organic layer was washed with brine, dried over sodium sulfate, filtered and evaporated. The residue was purified by silica gel chromatography eluting with PE/EA (15/1 to 4/1, v/v) to afford the title compound as a colorless amorphous solid. LC/MS m/z=468.0 [M+Na]+.
Wird geladen…