Design, synthesis, in vitro, and in silico studies of benzimidazolium derivatives as potent antimicrobial agents

In this study, twelve novel benzimidazolium derivatives (1–12) were synthesized and characterized using ¹H NMR and ¹³C NMR. The antimicrobial activity of the target compounds (1–12) was screened against five species of pathogenic bacteria and three fungal species (Escherichia coli (ATCC 25922), B. subtilis (ATCC 6633), E. faecalis (ATCC 29212), S. aureus (ATCC 29213), S. epidermidis (ATCC 12228) C. albicans (ATCC 24433), C. krusei (ATCC 6258), and C. parapsilopsis (ATCC 22019)). Voriconazole and Azithromycin were used as standards drugs. Results revealed that compound 1 was the most effective against C. albicans (ATCC 24433) strain with IC₅₀ value 3.90 µM. Furthermore, compound 5 was the most effective against S. aureus (ATCC 29213) strain with IC₅₀ value 7.81 µM. Scanning electron microscopy (SEM) was performed to distinguish differences on the surface of C. krusei in the absence and presence of compound 1. According to SEM results, it was found that pseudohyphal structures were disrupted and the surface was covered by the compound. In silico docking simulation studies to evaluate the molecular interactions of compound 1 was done with the sterol 14-alpha demethylase. The ADME pharmacokinetic properties of compound 1 were evaluated through in silico analysis using SwissADME. Additionally, the cytotoxic effects of the compounds on HUVEC cell line were studied.