Synthesis, Crystal Structures and Antibacterial Activity of Nickel(II), Cadmium(II) and Zinc(II) Complexes with Hydrazone Ligands

Three mononuclear nickel(II), cadmium(II) and zinc(II) complexes, [NiL2]·2CH3OH·H2O (1), [CdI2(HL)]·CH3OH (2) and [ZnL2] (3), have been synthesized from 3-hydroxy-4-methoxy-N'-[(Z)-(pyridin-2-yl)methylidene]benzohydrazide (HL) by microwave irradiation method. All complexes were characterized by CHN elemental analyses and infrared spectra. Structures of the complexes were further studied by single crystal X-ray determination, which reveals that the Ni and Zn atoms in complexes 1 and 3 are in octahedral coordination, and the Cd atom in complex 2 is in square pyramidal coordination. The biological activity of the complexes on the bacterial strains Bacillus subtilis, Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli was evaluated. As a result, the zinc complex has interesting antibacterial activities.