7beta-[2-(5-Amino-1,2,4-thiadiazol-3-yl)-2-ethoxyiminoacetamido]-3-(1-methyl-1-piperazinio)methyl-3-cephem-4-carboxylate 、
4,5-diacetoxy-2-pyridinecarbonyl chloride hydrochloride 、
碳酸氢钠 在
丙酮 作用下,
以
水 、
丙酮 为溶剂,
反应 2.5h,
以to give 7β-[2-(5-amino-1,2,4-thiadiazol-3-yl) -2-ethoxyiminoacetamido]-3-[1-methyl-4(4,5-dihydroxy-2-pyridylcarbonyl)-1-piperazinio]methyl-3-cephem-4-carboxylate (syn isomer) (155 mg)的产率得到7beta-[2-(5-Amino-1,2,4-thiadiazol-3-yl)-2-ethoxyiminoacetamido]-3-[1-methyl-4(4,5-dihydroxy-2-pyridylcarbonyl)-1-piperazinio]methyl-3-cephem-4-carboxylate