The present invention encompasses a method for the preparation of Telmisartan comprises, through Telmisartan dihydrochloride comprises i) Condensing 4-Methyl-2-n-propyl-1H-benzimidazole-6-carboxylic acid with N-Methyl-O-phenylenediamine dihydrochloride to yields 4-methyl-6 (1-methyl benzimidazol-2-yl)-2-n-propyl 1H-benzimidazole ii) Treating 4-methyl-6-(1-methylbenzimidazol-2-yl)-2-n-propyl-1H-benzimidazole with 4′-(bromomethyl)-2-biphenyl-2-carboxylate in presence of a base in an organic solvent and isolating the ester as acid addition salt iii) Converting ester acid addition salt to Telmisartan dihydrochloride and iv) Converting Telmisartan dihydrochloride to Telmisartan.
本发明涵盖一种制备坦索罗尔的方法,包括通过坦索罗尔二盐的形式,i)将4-甲基-2-n-丙基-1H-
苯并咪唑-6-
羧酸与N-甲基-O-
苯二胺二盐酸盐缩合,得到4-甲基-6-(
1-甲基苯并咪唑-2-基)-2-n-丙基-1H-
苯并咪唑;ii)在有机溶剂中,在碱的存在下,将4-甲基-6-(
1-甲基苯并咪唑-2-基)-2-n-丙基-1H-
苯并咪唑与4'-(
溴甲基)-2-
联苯基-2-
羧酸酯处理,并将酯分离为酸盐;iii)将酯酸盐转化为坦索罗尔二盐;iv)将坦索罗尔二盐转化为坦索罗尔。