Method for Preparing High-Purity Losartan
AssigneeZhejiang Huahai Pharmaceutical Co., Ltd.
InventorsXian Yang, Yang Zheng, Aixing Li, Jing Liu, Zunjun Liang, Fengfeng Yan
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Abstract
Disclosed in the present invention is a method for preparing high-purity losartan, which belongs to the fields of medicine and chemical engineering. The losartan is obtained by means of a multi-stage temperature reaction in the presence of a catalyst and sodium azide, wherein the temperature in the first stage of the multi-stage temperature reaction is higher than that in the second stage. According to the method, the generation of dimer impurities can be reduced, and the risk of impurities being introduced into a finished losartan potassium product is reduced. (I, II)
Claims17
A method for preparing losartan, comprising subjecting compound I to a multi-temperature-stage reaction in the presence of a catalyst and sodium azide to obtain losartan, wherein the temperature of a first stage of the multi-temperature-stage reaction is higher than that of a second stage,
A losartan composition, wherein the content of dimer L represented by formula III is less than 0.2%, and the content of dimer M represented by formula IV is less than 0.2%,
Dependencies are inferred from the claim text.