Green Synthesis of Benzimidazole Derivatives and Their Antimicrobial Evaluation: A Review

Author

Prithvi Rani AR, Dr. Sebastin V

Abstract

 Antimicrobial resistance and the environmental cost of conventional heterocyclic synthesis are two pressing problems in medicinal chemistry. Benzimidazole is a privileged scaffold with documented antibacterial and antifungal activity, but its classical syntheses often depend on strong acids, high temperatures, long reaction times, and organic solvents. This review summarises green synthetic approaches to benzimidazole derivatives, including water and solvent-free media, microwave and ultrasound activation, mechanochemistry, deep eutectic solvents and ionic liquids, and reusable heterogeneous and nanocatalysts, and relates them to reported antimicrobial evaluation. Structure–activity trends for antibacterial and antifungal activity and standardised methods for susceptibility testing are discussed. Current limitations include inconsistent reporting of green metrics, variation in assay methods between studies, and limited mechanistic and toxicity data. A stepwise strategy linking green synthesis, characterisation, antimicrobial screening, and early safety assessment is proposed.

Keywords

benzimidazole; green synthesis; antimicrobial activity; antibacterial; antifungal; microwave; deep eutectic solvents; nanocatalyst

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