1·The synthesis of Cilastatin sodium started from ethyl acetoacetate and 1-bromo-5-chloropentane, through 3 steps to produce ethyl 7-chloro-2-oxoheptanoate;
西司他丁钠的合成以乙酰乙酸乙酯和1-溴-5-氯戊烷为原料，经活性亚甲基烃化、成肟和水解3步反应得7-氯-2-氧庚酸乙酯；
2·METHODS The compound was synthesized through the reaction of cyclization, split, bromination et al and using 1,3-propyl bromide and ethyl acetoacetate as raw materials.
方法以1，3- 溴丙烷与乙酰乙酸乙酯为原料经环合、开环、溴代等反应合成。
3·Gas chromatography(GC) as a chemical reactor, methyl acetoacetate, ethyl acetoacetate, and methyl(3-oxo) pentanoate can undergo transesterfication with various alcohols without any catalyzers.
在气相色谱上，乙酰乙酸甲酯、乙酰乙酸乙酯、3-氧代戊酸甲酯与醇在无任何催化剂存在下，发生酯交换反应。