反应详情

A mixture of 7-[2-(2-aminothiazol-4-yl)-2-ethoxycarbonylmethoxyiminoacetamido]-3-vinyl-3-cephem-4-carboxylic acid (syn isomer) (1.45 g) and sodium bicarbonate (0.63 g) in water (15 ml) was stirred at ambient temperature for 7 days. The reaction mixture was adjusted to pH 6.0 with acetic acid. The solution was subjected to column chromatography on macroporous nonionic adsorption resin "Diaion HP-20" (30 ml) and eluted with water. The eluate was acidified to pH 2.2 with 10% hydrochloric acid under ice-cooling. The precipitates were collected by filtration and dried to give 7-[2-(2-aminothiazol-4-yl)-2-carboxymethoxyiminoacetamido]-3-vinyl-3-cephem-4-carboxylic acid (syn isomer) (0.7 g), which was identified by comparing the physico-chemical data with those of the object compound in Example 90.

1. wash" (30 ml) and eluted with water
2. temperaturecooling
3. filtrationThe precipitates were collected by filtration
4. customdried