METHOD FOR MANUFACTURING OLMESARTAN CILEXETIL HAVING CRYSTAL FORM

摘要

PURPOSE: A method for preparing olmesartan cilexetil of a crystalline form is provided to industrially synthesize the compound with stability. CONSTITUTION: A method for preparing olmesartan cilexetil of a crystalline form comprises: a step of reacting 4-(1-hydroxy-1-methylethyl)-2-propyl-imidazole-5-carboxylic acid and 1-chloroethyl cyclohexyl carbonate in a solvent to prepare 4-(1-hydroxy-1-methylethyl)-2-propyl-imidazole-5-carboxylic acid-1-cyclohexyloxycarbonylic-ethyl ester; a step of crystallizing using C1-C6 ether; a step of reacting the prepared compound with 2'-(tetrazole-5-yl)diphenyl-4-methylbromide in which NH of tetrazole is protected for crystallizing olmesartan cilexcetil; and a step of removing protection groups. The C1-C6 ether is ethyl ether, isopropylether, t-butyl ether, or ethyl propyl ether.