Downloads: 0
Research Paper | Chemistry | Volume 15 Issue 5, May 2026 | Pages: 1724 - 1729 | India
Synthesis, Characterization, and In Vitro Antimicrobial Activity of Some Transition Metal Complexes of a Novel Quinoline-Based Schiff Base
Abstract: This study describes the synthesis and characterization of a novel quinoline-based Schiff base ligand (DTQ), 3,3?-{1,3-phenylenebis[azanylylidene-(E)-methanylylidene]}di(quinoline-2-thiol), obtained through the condensation reaction of 2-mercapto-3-formyl-quinoline with 1,3-diaminobenzene in a 2:1 molar ratio. The progress of the reaction and purity of the synthesized compounds were monitored by thin-layer chromatography (TLC). The synthesized Schiff base ligand was subsequently employed for the preparation of its Cu(II), Ni(II), and Zn(II) metal complexes. The prepared ligand and its metal complexes were characterized by various physicochemical and spectroscopic techniques, including solubility studies, melting point determination, UV?Visible spectroscopy, FT?IR spectroscopy, magnetic susceptibility measurements, molar conductance analysis, atomic absorption spectroscopy (AAS), and elemental analysis. The low molar conductance values confirmed the non-electrolytic nature of the complexes. FT?IR spectral data revealed that the ligand coordinates to the metal ions through azomethine nitrogen and sulfhydryl sulfur donor atoms, forming tetradentate coordination sites. The Cu(II) and Ni(II) complexes exhibited paramagnetic behavior. The antimicrobial activity of the synthesized Schiff base and its metal complexes was evaluated using the disc diffusion method against selected Gram-positive bacteria, namely Bacillus subtilis and Staphylococcus aureus, Gram-negative bacteria including Pseudomonas aeruginosa and Escherichia coli, and fungal strains Candida albicans and Aspergillus niger at two different concentrations. All synthesized compounds exhibited noticeable antimicrobial activity against the tested microorganisms, with the Cu(II) complex showing the highest activity, displaying inhibition zones ranging from 19 to 23 mm.
Keywords: Quinoline, Schiff base, Tetradentate ligand, Metal complexes, Antimicrobial Activity
How to Cite?: Tushar S. Umasare, "Synthesis, Characterization, and In Vitro Antimicrobial Activity of Some Transition Metal Complexes of a Novel Quinoline-Based Schiff Base", Volume 15 Issue 5, May 2026, International Journal of Science and Research (IJSR), Pages: 1724-1729, https://www.ijsr.net/getabstract.php?paperid=SR26526141023, DOI: https://dx.dx.doi.org/10.21275/SR26526141023