A green synthesis of benzimidazoles

Abstract

Benzimidazole moieties are a very important class of heterocyclic compounds that have many applications in pharmaceutical chemistry 1 . Based on their broad biological functions 2 , they are used in clinical medicine 3 as anti-ulcer, anti-tumor and anti-viral agents 4 . Also, these are being developed as DNA minor groove binding agents that have significant anti tumor activity 5 . In addition, these compounds also seen as ligands for transition metals in model biological systems 6 and they have potential use for treatment of diseases such as ischemia-repersion injury 7a , hypertension 7b and obesity 7c . Several synthetic methodologies are available for the synthesis of benzimidazoles. Generally, the condensation of o-phenylene diamine with carboxylic acids and their nitrile, imidates and orthoester 8