Synthesis, characterization and in vitro antifungal elevation of novel benzimidazo [1,2-c]quinazolines

Abstract

The synthesis of a series of new benzimidazo [1,2-c]quinazolines starting from 2-nitrobenzaldehyde and o-phenylendiamine is decsribe. The structure elucidation of the products is based on detailed NMR analysis of experiments such as 'H-COSY,NOESY,DEPT,HSQC and HMBC. These compounds showed antifungal properties only against dermatophytes. Among them, those with electron-donor substituents on the 6-phenyl ring inhibitied mainly T. rubrum and E. floccossum with MICs between 25-250 ug/mL and M. canis, M. gypseum and T. mentagrophytes with MICs between 50-250 ug//mL. Structures with electron-witbdrawing substituents on the phenyl ring did not show any activities up to 250 ug//mL. Methyl substituents on the benzimidazole ring seem negatively affect the antifungal behaviour of this series.