Use of convertible isocyanides for the synthesis of benazepril hydrochloride

Herein, we have described a novel and concise synthesis of the potent angiotensin-converting enzyme (ACE) inhibitor, benazepril hydrochloride (7) in trifluoroethanol via an Ugi three-component reaction in shorter reaction times. The key step is the trifluoroacetic acid-mediated hydrolysis of secondary amides (4a and 4b) followed by esterification as a domino process to form corresponding ethyl ester (6). Mainly two universal convertible isocyanides (1a and 1b) were used for the synthesis of benazepril hydrochloride. Synopsis: An efficient synthesis of benazepril hydrochloride using Ugi three-component reaction.