反应详情

A solution of diazomethane in diethyl ether was added little by little to a solution of 4-nitrobenzyl 7-[2-(2-bromoacetyl)-2-hydroxyiminoacetamido]-3-cephem-4-carboxylate (0.9 g.) in tetrahydrofuran (30 ml.) under ice-cooling until the reaction terminated, and then acetic acid was added to the resultant solution to decompose excess diazomethane. The resultant solution was concentrated under reduced pressure to give the foamy product of 4-nitrobenzyl 7-[2-(2-bromoacetyl)-2-methoxyiminoacetamido]-3-cephem-4-carboxylate (syn-isomer: 0.9 g.)

1. temperaturecooling until the reaction
2. customterminated
3. additionacetic acid was added to the resultant solution
4. concentrationThe resultant solution was concentrated under reduced pressure