Patent ID: 7799928
Filing Date: 2010-09-21
Classification: A61P,C07D

Abstract:
1. A process for the preparation of irbesartan hydrochloride of formula (I) comprising reacting intermediate compounds 2n-butyl-1,3-diazaspiro [4,4] non-1-en-4-one of formula (II), optionally in salt form, and 5-(4′-bromomethyl-biphenyl-2-yl)-1-trityl-1 H-tetrazole of formula (III) where Hal represents bromo, chloro, fluoro or iodo, wherein reaction of intermediate compounds of formulae (II) and (III) results in formation of intermediate compound 2n-butyl-3[2′(triphenyl methyl tetrazol-5yl)-biphenyl-4-yl-methyl]-1,3-diazaspiro [4,4] non-1-en-4-one (trityl irbesartan) of formula (IV), optionally in salt form, which is subsequently detritylated, and, if necessary, converted to the hydrochloride salt, to yield irbesartan hydrochloride of formula (I) wherein the trityl irbesartan (IV) is not isolated before detritylation, and wherein trityl irbesartan (IV) is formed in the absence of an azide source.