Synthesis and Biological Evaluation of 1-Naphthyl and 4-Biphenyl Derivatives of 2, 4, 5-Trisubstituted-1H-Imidazoles as Antibacterial and Antifungal Agents

In current study, 2,4,5-trisubstituted-1H-imidazoles have been synthesized by starting from acid chloride preparation of various aromatic acetic acids (Ar’) such as 1-naphthyl acetic acid and 4-biphenyl acetic acid, which are used as such for the Friedel–Craft acylation (FCA) using various substituted aromatic nucleus (1a-b) (Ar) such as anisole, thioanisole etc and anhydrous aluminium trichloride to get various ethanone derivatives (2c-d). Methylsulfanyl group is converted into methylsulfonyl by refluxing former with glacial acetic acid and hydrogen peroxide to get ethanone derivatives containing methylsulfonyl moiety (2e-f). These ethanone derivatives (2a-f) were subjected to microwave irradiation for 90 secs to obtain diketones or ethanediones (3a-f). Ethanediones, in presence of acetic acid, ammonium acetate and benzaldehyde offered targeted compounds (4a-f). The structural elucidation of synthesized compounds was done using IR as well as ¹H NMR spectroscopy and biological screening for antibacterial action using E. coli and S. aureus and antifungal action using C. albicans and C. fumigatus was done using cup plate agar diffusion method.