Abstract Cefpirome was synthesized in 37.7% overall yield from 3-chloromethyl-7-phenylacetylamino cephalosporanic acid p-methoxybenzyl ester (GCLE) by sequential substitution of C-3 chloride with iodide and 2,3-cyclopentenopyridine, followed by a one-pot procedure including deprotection of carboxyl group, hydrolysis of 7-phenylacetamido, and reaction with 2-mercaptobenzothiazolyl-(Z)-2-(2-aminothiazol-4-yl)-2-methoxyiminoacetate (MAEM). The reaction conditions were as follows: obtained from GCLE at low temperature (−5 to 0 °C) and absence of light, 3-iodomethyl-7-phenylacetylamino cephalosporanic acid p-methoxybenzyl ester (GILE) without purification was reacted directly with 2,3-cyclopentenopyridine, in which the molar ratio of GCLE, NaI, and 2,3-cyclopentenopyridine was 1:2:4, and the molar ratio of the resulting compound p-methoxybenzyl 7-phenylacetylamido-3-(2,3-cyclopenteno-1-pyridinio)methyl-3-cephem-4-carboxylate iodide and MAEM was 1:1.1. The structure of the intermediate and the target compound obtained were determined by nuclear magnetic resonance spectra and mass spectroscopy.

中文翻译：

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GCLE 一锅法合成硫酸头孢匹罗

摘要 以 3-氯甲基-7-苯基乙酰氨基头孢烷酸对甲氧基苄酯 (GCLE) 为原料，通过用碘化物和 2,3-环戊烯吡啶依次取代 C-3 氯，然后采用一锅法合成了头孢匹罗，总产率为 37.7%。包括羧基的脱保护、7-苯基乙酰胺的水解以及与2-巯基苯并噻唑基-(Z)-2-(2-氨基噻唑-4-基)-2-甲氧基亚氨基乙酸酯(MAEM)的反应。反应条件如下：由GCLE在低温（-5至0°C）和无光下获得，未经纯化的3-碘甲基-7-苯乙酰氨基头孢烷酸对甲氧基苄酯（GILE）直接与2反应， 3-环戊烯吡啶，其中GCLE、NaI和2,3-环戊烯吡啶的摩尔比为1:2:4，所得化合物对甲氧基苄基7-苯基乙酰氨基-3-(2,3-环戊烯-1-吡啶基)甲基-3-头孢烯-4-羧酸碘化物与MAEM的摩尔比为1:1.1。所得中间体和目标化合物的结构通过核磁共振谱和质谱确定。