Eco-friendly synthesis and antifungal evaluation of N-substituted benzimidazoles

A convenient synthesis of N -phenacylbenzimidazoles in high yields (90–95%) by the N -alkylation reaction of 1 H -benzimidazole with phenacyl bromides is provided. The carbonyl group reduction in the products offered the respective N -(2-aryl-2-hydroxyethyl)benzimidazoles in yields up to 97%. In the optimization of reaction conditions for preparing these N -substituted benzimidazoles (ketones and alcohols), a comparative study between eco-friendly methods (microwave and ultrasound) and conventional heating is described. These antifungal azoles analogs were tested for in vitro antifungal activity against Candida albicans and Cryptococcus neoformans , where the alcohols chlorine substituted (4-Cl and 2,4-Cl 2 ) showed the best activity (MIC 50 = 31.2 × 10 –6 g/cm 3 ). Graphic abstract