Metal Complexes of Heterocyclic Schiff Bases: Synthesis, Spectral Characterization, and Antibacterial Evaluation
Keywords:
Heterocyclic Schiff Base; Metal Complexes; Transition Metal Ions; Spectral Characterization; FT-IR Spectroscopy; Antibacterial Activity; Coordination Chemistry.Abstract
Schiff bases containing heterocyclic moieties have attracted considerable attention because of their versatile coordination behavior and promising biological activities. In the present study, a heterocyclic Schiff base ligand was synthesized through the condensation of a heterocyclic aldehyde with a primary amine and subsequently complexed with transition metal ions such as Cu(II), Ni(II), Co(II), and Zn(II). The synthesized ligand and its metal complexes were characterized using FT-IR, UV–Visible spectroscopy, ^1H NMR, elemental analysis, and molar conductance measurements to confirm their structural and coordination properties. The antibacterial activity of the compounds was evaluated against selected Gram-positive and Gram-negative bacterial strains using the agar well diffusion method. The metal complexes exhibited enhanced antibacterial activity compared with the free Schiff base ligand, indicating that metal coordination improves biological efficacy. These findings suggest that heterocyclic Schiff base metal complexes possess significant potential as promising antibacterial agents for future pharmaceutical applications.
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