A new and simple process for the preparation of crystalline cimetidine (N-cyano-Nʹ-methyl-Nʺ-2/(5-methyl-1H-imidazole-4-yl)methylthio/ethyl}guanidine) is described wherein cimetidine is obtained by reacting O-ethyl-S-(4-methylimidazolyl-5-methyl)dithiocarbonate hydrobromide with N-cyano-Nʹ-methyl-Nʺ-(2-chloroethyl)guanidine in an aqueous methylamine solution at a temperature between room temperature and the reflux temperature of the reaction mixture, whereupon the desired compound is separated.
Cimetidine is a valuable drug in the therapy of the ulcer disease.
描述了一种制备结晶
西咪替丁(N-
氰基-Nʹ-甲基-Nʺ-2/(5-甲基-
1H-咪唑-4-基)甲
硫基/乙基}
胍)的简单新工艺,其中
西咪替丁是由 O-乙基-S-(
4-甲基咪唑-5-基)二
硫代
碳酸盐
氢溴酸盐与 N-
氰基-Nʹ-甲基-Nʺ-(2-
氯乙基)
胍反应而得。在室温和反应混合物回流温度之间的温度下,在
甲胺水溶液中使 O-乙基-S-(
4-甲基咪唑-5-甲基)二
硫代
碳酸氢溴酸盐与 N-
氰基-Nʹ-甲基-Nʺ-(2-
氯乙基)
胍反应、然后分离出所需的化合物。
西咪替丁是治疗溃疡病的一种重要药物。