Patent ID: 8912360

Claim:
A method for preparing ritodrine hydrochloride comprising: (a) reacting of 4-(2-bromopropionyl)phenyl methanesulfonate with benzyl-[2-(4-benzyloxyphenyl)-ethyl]-amine to obtain 4-(2{benzyl-[2-(4-benzyloxy-phenyl)-ethyl]-amino}-propionyl)-phenyl methanesulfonate; (b) hydrolyzing of 4-(2-{benzyl-[2-(4-benzyloxyphenyl)-ethyl]-amino}-propionyl) -phenyl methanesulfonate to obtain 2-{Benzyl-[2-(4-benzyloxyphenyl)-ethyl]-amino}-1-(4-hydroxy-phenyl)-propan-1-one; (c) salificating of 2-{Benzyl-[2-(4-benzyloxyphenyl)-ethyl]amino}-1-(4-hydroxy -phenyl-propan-1-one; and (d) catalytically hydrogenating of 2-{Benzyl-[2-(4-benzyloxyphenyl)-ethyl]-amino}-1-(4-hydroxy-phenyl)-propan-1-one hydrochloride to obtain Ritodrine hydrochloride as an erythro/threo mixture about of 98:2.