Syntheses, characterizations, crystal structures and antibacterial activities of two zinc(II) complexes with a Schiff base derived from o-vanillin and p-toluidine

Two new zinc(II) complexes, [Zn2L2Cl4]center dot 2[ZnL(CH3OH)Cl-2] 1 and [ZnL2(NO3)(2)] 2, were synthesized by reacting ZnX2.nH(2)O (X = Cl-, NO3-) and a Schiff base ligand 2-[(4-methylphenylimino)methyl]-6-metboxyphenol (C15H15NO2, L) which was obtained by the condensation of o-vanillin (2-hydroxy-3-methoxybenzaldehyde) with p-toluidine. Both 1 and 2 were characterized by single-crystal X-ray diffraction technique, elemental analysis, molar conductance, FT-IR, UV-Vis, H-1-NMR spectra and thermogravimetric analysis. The Schiff base ligand and its zinc(II) complexes have been tested in vitro to evaluate their antibacterial activity against bacteria, viz., Escherichia Coli, Staphylococcus aureus and Bacillus Subtilis. The results show that these complexes have higher activity than the corresponding free Schiff base ligand against the same bacteria.