Molecular geometry and biological activity of 2-(4-substituted-phenylimino)thiazolidin- 4-one compounds

Abstract

ABSTRACT. A series of 2-(4-substituted-phenylimino)thiazolidin-4-one compounds was synthesized via heterocyclizing the corresponding N-aryl-2-chloroacetamides with ammonium thiocyanate. Their chemical structures were elucidated based on an extensive analysis of their spectroscopic data, including infrared, ¹H NMR, ¹³C NMR, and mass analyses. The possible tautomeric forms of synthesized thiazolidine-4-ones were studied. The tautomerization equilibrium parameters, ΔH, ΔG, and K_eq were calculated using the DFT/B3LYP methodology, where it has been indicated that the tautomeric form, phenylimino, is more favourable than the phenylamino form. The antibacterial and antioxidant properties of the synthesized thiazolidin-4-ones were investigated. 2-(Chlorophenyl-imino)thiazolidin-4-one displayed  potent antibacterial  activity against E. coli (88.46%) and S. aureus (91.66%), and  highest percent of inhibition (81.8%, ABTS assay).

KEY WORDS: N-aryl-2-chloroacetamides, Ammonium thiocyanate, 2-(Arylimino)thiazolidin-4-ones, Mulliken’s charges, Dipole moment, ABTS assay

Bull. Chem. Soc. Ethiop. 2023, 37(5), 1275-1286.                                                           

DOI: https://dx.doi.org/10.4314/bcse.v37i5.18