Synthesis, characterization and antimicrobial evaluation of imidazolyl thiazolidinedione derivatives

Two series of 2,4 thiazolidinedione derivatives (T1–T4) and (T5–T8) containing substituted imidazoles and one series of 5-substituted 2,4-thiazolidinedione derivatives (T9–T12) were designed and synthesized. The chemical structures of all the three series of 2,4 thiazolidinedione derivatives have been elucidated by spectral studies (IR, 1H NMR, 13C NMR and Mass spectra). The compounds were screened for their anti-bacterial activity against Staphylococcus aureus ATCC-9144, Staphylococcus epidermidis ATCC-155, Escherichia coli ATCC-25922, Pseudomonas aeruginosa ATCC-2853 bacterial species and antifungal activity against Aspergillus niger ATCC-9029, Aspergillus fumigatus ATCC-46645 by the paper disc diffusion technique. The minimum inhibitory concentrations (MICs) of the compounds were also determined by the agar streak dilution method. Among the synthesized compounds methyl-2-(4-((3-(2-methoxy-2-oxoethyl)-2,4-dioxothiazolidine-5-ylidene) methyl)-1H-imidazol-1-yl) acetate (T2), methyl-2-(5-((1-(2-(4-fluorophenylthio)ethyl)-1H-imidazol-4-yl)methylene)-2,4-dioxo thiazolidin-3-yl)acetate (T4) and methyl-2-(2-((3-(2-methoxy-2-oxoethyl)-2,4-dioxothiazolidine-5-ylidene) methyl)-1H-imidazol-1-yl) acetate (T8) were found to possess moderately potent antimicrobial activity with MIC of 1.9, 1.4, 1.6, 0.56, 8.8, 2.3 μg/ml (T2), 3.8, 2.2, 1.6, 2.8, 7.9, 1.7 μg/ml (T4) and 2.7, 3.39, 3.2, 1.4, 8.2, 3.4 μg/ml (T8) against the above mentioned respective strains. All other compounds had shown mild to moderate antibacterial and antifungal activities. Keywords: Thiazolidinedione, Imidazole, Antibacterial, Antifungal, Antimicrobial evaluation