Background: Exposure of resistance by fungal and bacterial strains with respect to already existing antimicrobial agents is one of the crucial problems and also a motive to synthesize a new class of antimicrobial agents having potential activity in comparison with the commonly used therapy. The structurally interesting compounds for synthesizing antimicrobial agents are coumarin derivatives. Synthesis and screening of a series of new coumarin derivatives coupled with thiazole are performed for their antimicrobial properties. A series of new thiazolyl coumarin derivatives was synthesized upon refluxing 3-bromoaceytl coumarin, substituted benzaldehyde and thiosemicarbazide in presence of glacial acetic acid. Substituted 3-acetyl coumarin undergoes bromination in presence of bromine and chloroform to form 3-Bromoaceytl coumarin. The docking studies have been carried out against the enzyme DNA gyrase (1KZN).
Results: The thiazolyl coumarin derivatives were characterized on the basis of IR, 1H NMR and Mass spectral data. Compound SCT 2 showed the highest docking score -5.662 compared to other compounds. Screening of the final synthesized compounds were performed for their antibacterial activity by tube dilution method. Compound SCT 1 and SCT 2 showed significant antibacterial activity with minimum inhibitory concentration of 12.5µg/ml and 6.25µg/ml respectively compared to standard Cephalosporin.
The MIC results suggest that compounds SCT 1 and SCT 2 showed promising antibacterial activity. So these compounds are found to be interesting lead molecules for further synthesis as antimicrobial agents.
Keywords: Coumarin, thiazole, docking, antibacterial