反应详情

To a solution of 7-[2-(2-formamido-5-chlorothiazol-4-yl)-2-tert-butoxycarbonylmethoxyiminoacetamido]-3-cephem-4-carboxylic acid (syn isomer) (2.1 g) in methanol (50 ml) was added conc. hydrochloric acid (1.35 ml) at 32° to 35° C. The mixture was stirred for an hour at the same temperature. The resultant solution was adjusted to pH 5.0 with a saturated aqueous solution of sodium bicarbonate. After removing the solvent, the residual insoluble precipitates were collected by filtration. The precipitates were washed with water and dried over phosphorus pentoxide to give 7-[2-(2-amino-5-chlorothiazol-4-yl)-2-tert-butoxycarbonylmethoxyiminoacetamido]-3-cephem-4-carboxylic acid (syn isomer) (1.8 g), mp 180° to 185° C. (dec.).

1. customAfter removing the solvent
2. customthe residual insoluble precipitates
3. filtrationwere collected by filtration
4. washThe precipitates were washed with water
5. dry with materialdried over phosphorus pentoxide