ABSTRACT
A viable tactic to counteract drug-resistant bacteria is the creation of metal-based antimicrobial agents. Here, we present the synthesis and design of new coumarin–pyrazole compounds together with their coordination complexes with clioquinol and neodymium (III). After being produced via condensation, the ligands complexed with Nd (III) ions in the presence of Clioquinol to form stable chelates. Key bonding interactions were clarified, and effective coordination was validated by structural analysis employing FT-IR, NMR, and mass spectrometry (MS). With noticeably lower minimum inhibitory concentrations than the free ligands or metal salts alone, the resultant complexes demonstrated improved antibacterial activity against a spectrum of bacterial and fungal species. These findings point to a metal–ligand interaction-driven synergistic antibacterial mechanism that presents a viable framework for the creation of next-generation antimicrobial drugs.
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