反应详情

7-{2-(2-Formamido-4-thiazolyl)-2-methoxyiminoacetamido}-3-chloro-3-cephem-4-carboxylic acid (syn isomer, 0.4 g.) was suspended in methanol (15 ml.). After adding conc-hydrochloric acid (0.16 g.) to the suspension, the mixture was stirred at room temperature for 2.5 hours. Methanol was distilled off from the resultant mixture under reduced pressure, and the residue was dissolved in water (15 ml.). The solution was washed with ethyl acetate (30 ml.) and dichloromethane (30 ml.) in turn. To the acqueous layer was introduced nitrogen gas to remove the remaining organic solvent completely, and the solution was lyophilized to give 7-{2-(2-amino-4-thiazolyl)-2-methoxyiminoacetamido}-3-chloro-3-cephem-4-carboxylic acid hydrochloride (syn isomer 0.35 g.), m.p. 170° to 180° C. (dec.)

1. distillationMethanol was distilled off from the resultant mixture under reduced pressure
2. dissolutionthe residue was dissolved in water (15 ml.)
3. washThe solution was washed with ethyl acetate (30 ml.) and dichloromethane (30 ml.) in turn
4. additionTo the acqueous layer was introduced nitrogen gas
5. customto remove the remaining organic solvent completely