反应详情

An Aqueous solution of sodium hydroxide was carefully added dropwise to a stirred suspension of 7-[2-(2-aminothiazol-4-yl)-2-methoxyiminoacetamido]-3-cephem-4-carboxylic acid (syn isomer, 52 g.) in water (100 ml.) below 5° C. to make a solution of pH 7.0 to 7.5. After filtration and washing, the combined filtrate and the washings (200 ml.) was added dropwise to ethanol (2 l.) under stirring over 30 minutes, and stirring at room temperature for 15 minutes and then at 5° to 10° C. for an hour. The precipitates were collected by filtration, washed with ethanol (200 ml.) and dried in vacuo at 30° C. to give amorphous sodium 7-[2-(2-aminothiazol-4-yl)-2-methoxyiminoacetamido]-3-cephem-4-carboxylate (syn isomer, 46.3 g.).

1. filtrationAfter filtration
2. washwashing
3. additionthe combined filtrate and the washings (200 ml.) was added dropwise to ethanol (2 l.)
4. stirringstirring at room temperature for 15 minutes
5. waitat 5° to 10° C. for an hour
6. filtrationThe precipitates were collected by filtration
7. washwashed with ethanol (200 ml.)
8. customdried in vacuo at 30° C.