Study On The Synthesis Of New Antihypertensive Drug Telmisartan

Telmisartan, as a new benzimidazol angiotensin II receptor antagonist, was developed by Boehringer Ingelheim Co. and ratified by FDA for antihypertensive, with the characterstics of long-lasting, good tolerance and high receptor-selectivity.The project aims to study synthesis of telmisartan. Salicylic acid and 3-methyl-4-nitrobenzoic acid as the starting materials, telmisartan was synthesized successfully via a fifteen-step route with overall yields 13. 3%. Its structure was identified by the data of ~1H-NMR and MS.The intermediate(6) as the starting material, (8) was prepared by one-step reaction with the yield of 84.6%.This method has not been reported by far. To prepare the intermediate(6), the procedure was improved and the yields was raised.To prepare the intermediate(9), we reduced the reaction time from 20h to 12h with the same yield.(16') was made from (14) via two steps. This new method was simple and the yield was raised from 75% to 92%. And the intermediate (16') as the starting material, telmisartan was prepared. The yield of crude product was raised from 84. 6% to 90. 7%.