反应详情

A solution of 4-nitrobenzyl 7-amino-3-cephem-4-carboxylate (3.3 g.), trimethylsilylacetamide (6.4 g.) and bis(trimethylsilyl)acetamide (6.0 g.) in dry ethyl acetate (100 ml.) and a solution of dimethylformamide (0.9 ml.), phosphoryl chloride (1.1 ml.) and 2-(2-formamido-5-bromothiazol-4-yl)-2-methoxyiminoacetic acid (syn isomer, 5.1 g.) in dry ethyl acetate (5 ml.) were treated in a similar manner to that of Example 1-(1) (isopropyl alcohol was used for pulverization instead of diethyl ether) to give 4-nitrobenzyl 7-[2-(2-formamido-5-bromothiazol-4-yl)-2-methoxyiminoacetamido]-3-cephem-4-carboxylate (syn isomer, 2.65 g.).