Process for the preparation of febuxostat

摘要

An improved and efficient process for the preparation of 2-[3-cyano-4-(2-methylpropoxy)phenyl]-4-methylthiazole-5-carboxylic acid (febuxostat) that is substantially free from amide by-product is provided.

主权项

1. A process for the preparation of febuxostat of Formula I comprising the steps of: (i) reacting 4-hydroxy thiobenzamide of Formula II with a compound of Formula III (wherein X is halogen and R is alkyl or arylalkyl) to give a compound of Formula IV; (ii) formulation of the compound of Formula IV with hexamethylene tetramine in presence of an acid to give a compound of Formula V; (iii) reaction of the compound of Formula V with hydroxylamine hydrochloride to give a compound of Formula VI; (iv) alkylation of the compound of Formula VI with isobutyl halide of Formula VII (wherein X is halogen) to give a compound Formula VIII; and (v) hydrolysis of the compound of Formula VIII in the presence of barium oxide.