Design, Synthesis and Molecular Docking Studies of Novel Pyrazole Benzimidazole Derivatives as Potent Antibacterial Agents

Abstract

A novel series of pyrazole benzimidazole derivatives were synthesized and the structure of the final targets 4a-h were confirmed by IR, Mass, 13C NMR and 1H NMR spectral analysis. The new pyrazole core with imidazole and benzimidazoles derivatives were evaluated for in vitro antibacterial, antifungal activity against six bacterial strains significantly. In dispersion, 4c, 4f and 4g had the highest antibacterial activities on these microorganisms Bacillus subtilis B29, Escherichia coli E266, with zone of inhibition 21, 19 and 19 mm, respectively. Compounds 4a, 4c, 4h shows good antifungal activity against A. niger, Fusarium oxysporum fungal strains. Further, molecular docking for protein ligands interactions was performed using the crystal structure of C(30) carotenoid dehydrosqualene synthase from Staphylococcus aureus complexed with bisphosphonate BPH-700. Among the final compounds 4e, 4g and 4h show highest binding energy ΔG = -7.89, -7.48 and -7.08 Kcal/mol, respectively and amino acid interactions Lys273, Asp27.