反应详情

To a solution of benzhydryl 7-[2-benzhydryloxycarbonylmethoxyimino-2-(2-aminothiazol-4-yl)acetamido]-3-vinyl-3-cephem-4-carboxylate (syn isomer) (3 g) in formic acid (12 ml) was added 35% hydrochloric acid (1 ml) at 0° C. After stirring at ambient temperature for an hour, the reaction mixture was poured into diisopropyl ether. The precipitates were collected by filtration, washed with diisopropyl ether and then dissolved in water (15 ml). The aqueous solution was adjusted to pH 3.5 with 5% aqueous sodium bicarbonate. The precipitates were collected by filtration and dried to give 7-[2-carboxymethoxyimino-2-(2-aminothiazol-4-yl)acetamido]-3-vinyl-3-cephem-4-carboxylic acid (syn isomer) (1.5 g).

1. filtrationThe precipitates were collected by filtration
2. washwashed with diisopropyl ether
3. dissolutiondissolved in water (15 ml)
4. filtrationThe precipitates were collected by filtration
5. customdried