Quinoxaline Clubbed Thiazole: Molecular Docking, Synthesis and Antimicrobial Evaluation

Novel hybrid molecules of thiazole with quinoxaline have been designed, synthesized and characterised by FT-IR, Mass, 1H and 13C NMR spectroscopic techniques. The pharmacological potential of synthesised compounds was checked for bacterial and fungal strains by the Broth microdilution method. All molecules exhibited significant antibacterial and antifungal activities. The compound (E)-4-(4-chlorophenyl)-2-(2-(1-(3-methylquinoxalin-2-yl)ethylidene)hydrazinyl)thiazole (3b) displayed (MIC = 12.5 μg/mL) excellent biological potential against Staphylococcus aureus [MTCC96] gram-positive bacterial strain. The molecular docking of thiazole derivatives was performed with S. aureus DNA gyrase (2XCT). The docked molecules displayed significant interactions with the active cavity of S. aureus DNA gyrase. The (E)-4-(4-chlorophenyl)-2-(2-(1-(3-methylquinoxalin-2-yl)ethylidene)hydrazinyl)thiazole (3b) molecule displayed the most stable conformation at the highest binding affinity (-10.9 kcal/mol) among the docked molecules with protein.