反应详情

To a solution of (3R,5S)-1-(tert-butoxycarbonyl)-5-[{[6-fluoro-1-(4-methoxybutyl)-1H-benzimidazol-2-yl]carbonyl}(2-methylpropyl)amino]piperidine-3-carboxylic acid (274 mg) and 4-methylmorpholine (66 μl) in THF (5 ml) was added dropwise ethyl chlorocarbonate (57 μl) at 0° C., and the mixture was stirred at the same temperature for 1 hr. Sodium borohydride (57 mg) and methanol (1 ml) were added to the reaction mixture, and the mixture was stirred at 0° C. for 1 hr. The reaction mixture was diluted with aqueous sodium bicarbonate, and the mixture was extracted with ethyl acetate. The extract was washed with saturated brine, and dried over anhydrous sodium sulfate. The solvent was evaporated under reduced pressure. The residue was subjected to basic silica gel column chromatography, and a fraction eluted with ethyl acetate was concentrated under reduced pressure to give the object product (182 mg).

1. stirringthe mixture was stirred at 0° C. for 1 hr
2. extractionthe mixture was extracted with ethyl acetate
3. washThe extract was washed with saturated brine
4. dry with materialdried over anhydrous sodium sulfate
5. customThe solvent was evaporated under reduced pressure
6. washa fraction eluted with ethyl acetate
7. concentrationwas concentrated under reduced pressure