Improved methods for the synthesis of irbesartan, an antihypertensive active pharmaceutical ingredient

摘要

New methods for the preparation of irbesartan 1 have been described. The dehydration and tetrazole formation in one step from substituted cyclopentane derivative 7 with tributyltin chloride and sodium azide is described. Selective hydrolysis of nitrile 3 with HCl has also been described in the preparation of N-acylaminocyclopentane-2- carboxylic acid 4, which is the key intermediate for the preparation of irbesartan. The impurity profiling of irbesartan has also been discussed.