Synthesis of new pyrazine-pyrazole-thiazolidin-4-one and pyrazine-triazole-thiazolidin-4-one conjugates, molecular modelling and docking as antimicrobial agents

The ever-increasing incidence of microbial resistance provide a significant peril to the scientific community. Thus, the need for the discovery and development of new antimicrobial agents is becoming critical. An effective approach to address this challenging problem is to generate hybrid molecules by combining two or more pharmacophores covalently linked to a single-molecule platform. Antimicrobial hybrids have been proposed as promising solution to overcome drug resistance and/or presumably having a broader spectrum of activity. This guided us to synthesize a new series of eight final target pyrazine-pyrazole-thiazolidin-4-one and pyrazinetriazole-thiazolidin-4-one hybrids 7, 8a-c, 12, and 13a-c and investigate their biological activities. Characterization of the designed hybrids were performed using IR, 1H NMR, 13C NMR, and mass analyses. The DFT/B3LYP approach revealed that the synthesized hybrids had a non-planar configuration. The nitrobenzylidene derivatives 8c and 13c exhibited the highest polarizability and hyperpolarizability. We examined the antimicrobial activity, DNA gyrase inhibition, molecular docking, and Swiss ADME analysis of different pyrazine-pyrazole-thiazolidin4-one and pyrazine-triazole-thiazolidin-4-one conjugates. These compounds are effective against a number of bacterial and fungal strains, suggesting possible treatments for certain infections. DNA gyrase inhibition experiments demonstrated that conjugate 13b was more effective than novobiocin. A molecular docking study sheds light on the binding affinities and interactions of these conjugates with target proteins, revealing strong and specific bindings for numerous conjugates. Swiss ADME studies examine important pharmacokinetic parameters and show issues with bioavailability and membrane permeability in the mouth because of variations in molecular weight, lipophilicity, and hydrogen bond interactions. Swiss ADME studies have studied the drug-like qualities of these conjugates, revealing their potential in antibacterial applications.