الفهرس | Only 14 pages are availabe for public view |
Abstract The thiosemicarbazone, HL, ligand was prepared by the condensation reaction of 2-aminochromone-3-carboxaldehyde with thiosemicarbazide. The thiosemicarbazone ligand acts as tridentate (NOS) ligand. The structure of the ligand was elucidated by elemental analyses, IR, 1H-NMR, 13C-NMR, mass, and electronic spectra. Reaction of the thiosemicarbazone ligand with copper(II), nickel(II), cobalt(II), zinc(II), iron(III) and vanadyl(IV) ions in a molar ratio 1:1 afforded the corresponding binary complexes. The ternary complexes were prepared by the reaction of the ligand and the metal ions and the secondary ligand: N,O-donor [8-hydroxyqinoline (8-HQ) and glycine (Gly)] or N,N-donor [1,10-phenanthroline] in the molar ratio 1:1:1. All reactions afforded monnuclear complexes. The structures of the newly prepared complexes were identified by elemental analyses, infrared, electronic, mass, 1H-NMR and ESR spectra as well as molar conductance, magnetic susceptibility measurements and thermal gravimetric analysis (TGA). The thiosemicarbazone ligand behaves as neutral or monobasic tridentate chelating sites via γ-pyrone oxygen, azomethine nitrogen and the thionic/thiolic sulfur. The metal complexes exhibit monomeric structures with different geometrical arrangements such as octahedral, square planar, tetrahedral, and square pyramidal arrangements. The prepared ligand and its metal complexes were screened for their antimicrobial activity and revealed variable inhibition activity against the tested Gram-positive bacteria, Gram-negative bacteria and the fungal strains. |