Synthesis, characterization and antimicrobial properties of silver complexes derived from 5,6-Dimethylbenzimidazol-2-ylidene

Abstract

Benzimidazoles are considered as a class of bioactive heterocyclic compounds that exhibit many biological ac-tivities such as antimicrobial. Benzimidazole-silver complexes also have strong antimicrobial activity, sometimes even higher than that of conventionally used silver antimicrobials. In this study, six new 5,6-dimethylbenzimi-dazolium ligand precursors which were functionalized by using 2-naphthylmethyl and their silver complexes were synthesized. All molecules were characterized by elemental analysis, 1H NMR, 13C NMR, and IR spec-troscopy techniques. Additionally, mu-Dichloro-bis{[1-(2-naphthylmethyl)-3-(benzyl)-5,6-dimethylbenzimidazol-2-ylidene]silver(I)} was characterized structurally in the solid state by X-ray crystallography which was found to be dimeric with two bridging chlorides. In vitro antimicrobial activity of the synthesized compounds investigated in this work was tested against the reference strains: Escherichia coli (ATCC 25922), Staphylococcus aureus (ATCC 29213) and Pseudomonas aeruginosa (ATCC 27853), Candida albicans (ATCC MYA-2876) and Candida glabrata (ATCC 2001). Some of these new compounds have been found to display significant effectiveness. Also, the molecular docking analysis was performed for all optimized ligands and complexes against SarA