Published Paper Details:

Abstract : A new antimony(III) complex with a salicylaldehyde-based N-thiohydrazone ligand has been synthesized and characterized. The Schiff base ligand, salicylaldehyde-p-toluidine-N-thiohydrazone (HSalptth), was prepared by the condensation of salicylaldehyde with p-toluidine-N-thiohydrazide and isolated as a cream-white crystalline solid. Reaction of the ligand with antimony trichloride in methanol afforded the bis(salicylaldehyde-p-toluidine-N-thiohydrazonato)antimony(III) complex, [Sb(Salptth)(HSalptth)], as a white granular precipitate. The ligand and its antimony(III) complex were characterized by elemental analysis, molar conductance, magnetic susceptibility, and spectroscopic techniques including FT-IR, UV-Visible, and ^1H NMR spectroscopy. Spectral studies indicate coordination of the ligand to the Sb(III) center through the azomethine nitrogen and thiolate sulfur atoms, suggesting a bidentate chelating mode. The complex is found to be non-electrolytic in nature and exhibits a distorted coordination geometry around the antimony(III) ion. The biological activity of the ligand and its antimony(III) complex was evaluated against selected bacterial and fungal strains. The antimony(III) complex shows enhanced antimicrobial activity compared to the free ligand, which may be attributed to increased lipophilicity upon chelation. These results highlight the potential of salicylaldehyde-based thiohydrazone complexes of antimony(III) as biologically active coordination compounds.