Novel coumarin-thiazolyl ester derivatives as potential DNA gyrase Inhibitors: Design, synthesis, and antibacterial activity.

The design and synthesis of novel coumarin-thiazolyl ester derivatives of potent DNA gyrase inhibitory activity were the main aims of this study. All the novel synthesized compounds were examined for their antibacterial activity against Staphylococcus aureus, Listeria monocytogenes, Escherichia coli and Salmonella. Compound 8p exhibited excellent antibacterial activity against four bacteria strains with MIC values of 0.05, 0.05, 8, and 0.05 μg/mL, respectively. In vitro drug-resistant bacterial inhibition experiments indicated that compound 8p exhibited the best bacteriostatic effect in the selected compounds and four positive control drugs with MIC values of 4 μg/mL. In vitro enzyme inhibitory assay showed that compound 8p exhibited potent inhibition against DNA gyrase with IC50 values of 0.13 μM. The molecular docking model indicated that compounds 8p can bind well to the DNA gyrase by interacting with amino acid residues. This study demonstrated that the compound 8p can act as the most potent DNA gyrase inhibitor in the reported series of compounds and provide valuable information for the commercial DNA gyrase inhibiting bactericides.