反应详情

7-{2-(2-Formamido-4-thiazolyl)-2-methoxyiminoacetamido}-3-cephem-4-carboxylic acid (syn isomer, 95 mg.) was suspended in methanol (4 ml.). To the suspension was added conc. hydrochloric acid (110 mg.) and the solution was stirred at room temperature for 4 hours. After distilling methanol under reduced pressure, the residue was dissolved in water (30 ml.) and the aqueous solution was washed with ethyl acetate (10 ml.) and dichloromethane (15 ml.) in turn. Nitrogen gas was introduced into the aqueous solution to exclude the remaining organic solvent, and the aqueous solution was lyophilized to give 7-{2-(2-amino-4-thiazolyl)-2-methoxyiminoacetamido}-3-cephem-4-carboxylic acid hydrochloride (syn isomer, 83 mg.), m.p. 180° to 190° C. (dec.).

1. distillationAfter distilling methanol under reduced pressure
2. dissolutionthe residue was dissolved in water (30 ml.)
3. washthe aqueous solution was washed with ethyl acetate (10 ml.) and dichloromethane (15 ml.) in turn
4. additionNitrogen gas was introduced into the aqueous solution