Abstract: “Benzimidazole derivatives are crucial structural heterocyclic motifs found in diverse libraries of biologically active compounds which are therapeutically useful agents in drug discovery and medicinal research. 2-(3,5-Dinitrophenyl) benzimidazole, 1 was synthesized by [4+1]-cycloaddition of o-phenylenediamine with 3,5-dinitrobenzoic acid in catalytic amount of NH4Cl. Compound 1 was subsequently utilized as precursor which upon reaction with some halogenated molecular entity furnished the targeted N-substituted-2-(3,5-dinitrophenyl) benzimidazole derivatives in improved yields after reaction optimization engagement. The progress of reaction was monitored with TLC and the chemical structures were confirmed by analytical data and spectroscopic means such as UV, IR, mass spectra, 1H NMR, 13C NMR and DEPT-135. The titled compounds were screened for their antimicrobial activity alongside with gentamicin standard drug, using agar diffusion method while the minimum inhibitory concentration (MI”

Keywords: Antibacterial, catalysis, cyclo-addition, benzimidazole, spectroscopy, chromatography