Fremgangsmåde til fremstilling af Telmisartan

摘要

Preparation of telmisartan (A) involves reacting 2-n-propyl-4-methyl-6-(1-methyl-benzimidazol-2-yl)-benzimidazole (I) with a 4-(substituted methyl)-2'-cyanobiphenyl (IV), then hydrolyzing the cyano group of the obtained 2-cyano-4'-(2-n-propyl-4-methyl-6-(1-methyl-benzimidazol-2-yl)-benzimidazol-1-ylmethyl)-biphenyl (V). Preparation of telmisartan (A) involves reacting 2-n-propyl-4-methyl-6-(1-methyl-benzimidazol-2-yl)-benzimidazole(I) with a biphenyl derivative of formula (IV), then subjecting the 2-cyano-4'-(2-n-propyl-4-methyl-6-(1-methyl-benzimidazol-2-yl)-benzimidazol-1-ylmethyl)-biphenyl (V) (optionally after work-up) to hydrolysis of the cyano group to give the corresponding acid (A), which is optionally converted into the hydrochloride during work-up. [Image] Z' : leaving group, preferably halo (especially Br) or substituted sulfonyloxy. ACTIVITY : Hypotensive. MECHANISM OF ACTION : Angiotensin II receptor antagonist.