فهرست نشریات علمی دسترسی آزاد ایران

This review highlights recent progress (2020–2025) in understanding the antimicrobial potential of Schiff base ligands and their Zn(II) complexes. The discussion begins with an overview of the synthesis and structural characterization of these complexes. Typically, Schiff bases—formed via the condensation of aldehydes/ketones with primary amines—coordinate with Zn(II) ions to yield complexes exhibiting diverse geometries such as tetrahedral, square-planar, square-pyramidal, trigonal-bipyramidal, and octahedral. These structural arrangements have been elucidated through various spectroscopic techniques and X-ray crystallography. The review then examines their antimicrobial performance against a wide range of Gram-positive and Gram-negative bacterial strains, as well as selected fungi. A consistent trend across the literature indicates that coordination with Zn(II) markedly enhances antimicrobial efficacy compared with the free ligands. This improvement is commonly explained by Tweedy’s chelation theory, which proposes that metal coordination increases the lipophilicity of the complex, thereby facilitating greater membrane permeability and interference with vital microbial processes. Overall, the findings emphasize Zn(II)–Schiff base complexes as promising and versatile scaffolds for the design of next-generation antimicrobial agents. Their biological performance is strongly influenced by structural and electronic features, highlighting the importance of molecular design in future therapeutic development.