VO(IV) Complexes of N2O2 Tetra Dentate Ligands With Flexible Alkyl Spacer: Synthesis, Characterization and Antibacterial Activities

Abstract

1,4-diaminobutane was synthesized with 2-furan-carboxyaldehyde using Schiff base condensation method leading to a new ligand containing N₂O₂ donor. The same reaction path was followed replacing 1,4-diaminobutane by 1,6-diaminohexane and 1,8-diaminooctane in separate reactions to obtain the two other new ligands. Then, the synthesized ligands were employed to attain the Oxo-vanadium(IV) complexes as results of their reactions with VOSO₄.H₂O. The ligands were characterized by FT-IR, ¹³C-NMR, ¹H-NMR, LC ESI/MS. The VO(IV) complexes were elucidated by FT-IR, energy dispersive x-ray spectrum (EDX), thermogravimetric (TG) methods and the conductivity and magnetic susceptibility measurements. The antibacterial activities of the ligands and their complexes were determined on the microorganisms which can be aligned as Escherichia coli ATCC 25922, Salmonella thphimurium ATCC 14028, Staphylococcus aureus ATCC 25923, Listeria monocytogenes ATCC 19115 and Bacillus cereus ATCC 11778. The complexes, in general, appeared to be more active than their parent ligands. All the activities can be classified as moderate in comparison with the corresponding antibiotic effect on the same bacteria.