890708-64-2Relevant academic research and scientific papers
PROCESS FOR THE PREPARATION OF TAMSULOSIN AND INTERMEDIATES THEREOF
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Page/Page column 13, (2008/06/13)
A process for producing tamsulosin of formula (I) and pharmaceutically acceptable addition salts, thereof comprises the steps of : a) Reacting compound R,R-[2-(4-methoxy-phenyl)-1-methyl-ethyl]-(1-phenyl-ethyl)-amine of formula (II) or a salt thereof (II) with chlorosulfonic acid with or without an organic solvent, to obtain compound R,R-2methoxy-5-[2-(1-phenyl-ethylamino)-propyl]-benzenesulfonic acid of formula (III) b) Hydrogenolysis of compound R,R-2-methoxy-5-[2-(1-phenyl-ethylamino)-propyl]- benzenesulfonic acid of formula III or a salt thereof carried out in an alcohol in the presence of a palladium catalyst using hydrogen or a source of hydrogen, to obtain compound R-(-)-5-(2-amino-propyl)-2-methoxy-benzenesulfonic acid of formula (IV) c)Reacting primary amine R-(-)-5-(2-amino-propyl)-2-methoxy-benzenesulfonic acid of formula (IV), or a salt thereof, with a compound of formula (V) wherein X represents an halogen atom selected from the group consisting of C1;Br and I, to obtain 5- [(2R)-2-[2-(2-ethoxy-phenoxy)-ethylamino]-propyl]-2-methoxy-benzenesulfonic acid compound of formula (VI) d) Reacting compound of formula (VI) with an halogenating agent, to obtain the corresponding sulfonylchloride of formula (VII). e)Reacting compound VII with ammonia to obtain compound I.
