+44 1625708989Synthesis, characterization, and antimicrobial studies of some vanillin schiff base metal (II) complexes
Author(s): M. B. Fugu, N. P. Ndahi, B. B. Paul and A. N. MustaphaSome new transition metal complexes of Mn(II), Co(II), Ni(II), Cu(II) and Zn(II) with Schiff base ligand (HL) derived from condensation of vanillin with 2-aminophenol was synthesized in alcoholic medium. Both the ligand/complexes were characterized on the basis of microanalysis, melting point, conductivity, solubility, IR, and UV/VIS spectral studies. The in vitro antibacterial activities of the complexes were tested using number of bacteria species such as Escherichia coli, Salmonella typhi, Klebsiella pneummiae, Pseudomonas aeruginosa, Staphylococcus aureus, Streptocuccus pyogenes, corynebacterium specie, and Basillus subtilis. The complexes were formed in moderate yields and they are of various colours and have sharp melting points. The purity and composition of the Schiff bases and the metal(II) complexes were established by elemental analysis which suggests a metal: ligand ratio of 1:2. The IR spectra revealed that the complexes coordinated through azomethine nitrogen and methoxy oxygen of the ligands. Further conclusive evidence of the coordination of the Schiff bases with the metal ions was shown by the appearance of new bands due to v(M-N) and v(M-O) in the metal complexes. Based on the electronic spectral transitions, an octahedral structure has been assigned to all the complexes except Zn(II) complexes which has been assigned tetrahedral structure. Measured molar conductance showed that the complexes are non electrolytes and are soluble in protic solvents like methanol and ethanol. Some complexes showed good antibacterial activities against the tested bacteria at 100, 200 and 300 mg/ml. therefore, the possible use of the complexes as antibiotic can be suggested.
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