反应详情

温度

22 °C

A mixture of 2-(2-formamidothiazol-4-yl)acetic acid (0.70 g), 2,6-lutidine (0.44 ml), triethylamine (0.05 ml) and pivaloyl chloride (457 mg) in dry methylene chloride (10 ml) was stirred at -15° C. for 20 minutes, at 12° C. for 20 minutes and at 22° C. for a further 40 minutes. A mixture of benzhydryl 7-amino-3-(4-methyl-1-piperazinyl)carbonyloxymethyl-3-cephem-4-carboxylate-1-oxide (1.7 g) in methylene chloride (20 ml) was cooled to -30° C. and thereto was added the acid anhydride solution obtained above followed by stirring at -20° to -10° C. for an hour and at -10° C. to ambient temperature for a further one hour. The reaction mixture was evaporated and to the residue was added ethyl acetate (20 ml) and water (10 ml) followed by stirring. Insoluble substances were collected by filtration, washed with water and ethyl acetate and then dried under reduced pressure to give benzhydryl 7-[2-(2-formamidothiazol-4-yl)acetamido]-3-(4-methyl-1-piperazinyl)carbonyloxymethyl-3-cephem-4-carboxylate-1-oxide (1.75 g).

1. temperaturewas cooled to -30° C.
2. customobtained
3. stirringby stirring at -20° to -10° C. for an hour and at -10° C. to ambient temperature for a further one hour
4. customThe reaction mixture was evaporated and to the residue
5. additionwas added ethyl acetate (20 ml) and water (10 ml)
6. stirringby stirring
7. filtrationInsoluble substances were collected by filtration
8. washwashed with water and ethyl acetate
9. customdried under reduced pressure