反应详情

A mixture of benzhydryl 7-[2-tert-butoxycarbonylmethoxyimino-2-(2-formamidothiazol-4-yl)acetamido]-3-vinyl-3-cephem-4-carboxylate (syn isomer)(19.0 g) and conc. hydrochloric acid (11.6 g) in methanol (380 ml) was stirred at ambient temperature for 15 minutes. After addition of water (200 ml), the reaction mixture was neutralized with sodium bicarbonate, followed by removing the methanol under reduced pressure. The resultant aqueous solution was extracted three times with ethyl acetate, and the combined extract was washed with water and an aqueous solution of sodium chloride, and then dried over anhydrous magnesium sulfate. Removal of the solvent gave an oil, which was pulverized with diisopropyl ether to obtain benzhydryl 7-[2-(2-aminothiazol-4-yl)-2-tert-butoxycarbonylmethoxyiminoacetamido]-3-vinyl-3-cephem-4-carboxylate (syn isomer)(15.3 g).

1. customby removing the methanol under reduced pressure
2. extractionThe resultant aqueous solution was extracted three times with ethyl acetate
3. extractionthe combined extract
4. washwas washed with water
5. dry with materialan aqueous solution of sodium chloride, and then dried over anhydrous magnesium sulfate
6. customRemoval of the solvent
7. customgave an oil, which