Patent ID: 8273918
Filing Date: 2012-09-25
Classification: C07C

Abstract:
1. An improved process to prepare Tamsulosin hydrochloride of Formula I which comprises (i) reacting (R)-(−)-5-(2-aminopropyl)-2-methoxybenzenesulfonamide of Formula II, with substituted phenoxy compound of Formula III, wherein Z represents a leaving group selected from —OSO 2 CH 3 , —SO 2 C 6 H 4 CH 3 , —F, —Br, —Cl, or —I, in a solvent in the presence of an alkaline earth metal oxide to obtain Tamsulosin base; and (ii) converting Tamsulosin base into hydrochloride salt in a solvent by addition of aqueous hydrochloric acid.