Selenium N-heterocycic carbene compounds and their biological properties

The resistance of bacteria and yeasts to most drugs has led researchers to find new, more effective drugs. Carbenes play an important role in various reactions in organic chemistry, especially in addition and rearrangement processes. Many heterocyclic carbene complexes have been found to have important biological activities as antimicrobial, antioxidant and anticancer agents. Selenium is an essential micronutrient that is non-toxic to humans at low concentrations. Selenium-containing compounds are promising candidates in drug research due to their ability to alter various physiological functions. Selenium-N-heterocyclic carbene (NHC) compounds offer anticancer, antimicrobial, antioxidant, anti-inflammatory, antiviral, antineurodegenerative, antidepressant, antineoplastic activities. In this study, new carbene compounds (1a-h) were synthesized by coupling alkyl groups containing different bulky and functional components to 1-(2,2-diethoxyethyl) benzimidazole. Se-NHC compounds (2a-h) were synthesized by interacting these precursor benzimidazolium salts with selenium. The structures of the precursor imidazolium salts and Se-NHC compounds were elucidated by 1H NMR, 13C NMR and microanalysis methods. The antimicrobial activities of the synthesized compounds were investigated against C. albicans and C. glabrata yeasts, E. coli, S. aureus and P. aeruginosa bacteria and MIC (μg/ml) values were calculated.