Metal-Salen Complexes: Structural Characterization and Antibacterial Activity

Abstract

The ligand, N,N'-bis(salicylidine)ethylenediamine or salen (L), and its complexes 1-3 with Ni(II), Cu(II) and Mn(II) were synthesized. Various analytical methods such as microanalysis, 1H-NMR, 13C-NMR, ESI-MS and FT-IR spectroscopy has been used to characterize the synthesized compounds. Antibacterial activity of the prepared compounds were tested against two Gram-positive bacteria Staphylococcus aureus and Bacillus subtillus and two Gram-negative bacteria Pseudomonas aeroginosa and Escherichia coli by agar well diffusion method. Antibacterial screening results indicate that the metal compounds are more biologically active than the free ligand. The variation of metal ions appears to influence their antibacterial activity toward different organisms. The mode of action of the synthesized metal complexes as antibacterial agents have also been explained.