Reevaluating the synthesis of 2,5-disubstituted-1H-benzimidazole derivatives by different green activationtechniques and their biological activity as antifungal andantimicrobial inhibitor

Abstract

A comparative study concerned with the preparation of diversely substituted-1H-benzimidazole under different green activation techniques and conven-tional methods is reported. Data are collected for infrared, ultrasound, micro-wave, and simultaneous irradiation with US and IR sources, as this laststrategy shows an important improvement. Further, the small library ofpotentially bioactive benzimidazole17-76synthesized was screened as an anti-fungal and antimicrobial agent. Strong activity againstCandida albicansandStaphylococcus aureuswas observed. Remarkably, 2-(4-aminophenyl)-5-phenylamino-1H-benzimidazole63resulted better than that of referencedrugs miconazole with a zone of inhibition up to 42 mm. Likewise,2-(2-aminophenyl)-1H-benzimidazole21showed substantial antimicrobialactivity against MRSA strain. When assayed by the microdilution method, thisazaheterocyclic compound presented a minimum inhibitory concentration(MIC)≥16.4μg/100 mL and a bacterial percentage reduction of 96%.