Spectral characterization, crystal structures and biological activities of iminodiacetate ternary complexes.

The ternary complexes with stoichiometry [M(imda)(bipy)]·6H 2 O (M = Cu) and [M(imda)(bipy)(H 2 O)]·4H 2 O (M = Ni, Co and Mn) where H 2 imda = iminodiacetic acid and bipy = 2,2′-bipyridine, are prepared and characterized to exploit as novel antimicrobial agents and SOD mimics. The chemical structures were elucidated by IR, FAB-Mass, 1 H, 13 C NMR, EPR and spectral techniques. Single crystal X-ray and spectral studies of the complexes ( 1 ) and ( 2 ) have confirmed a square pyramidal geometry around Cu(II) ion while a saturated six coordinate (distorted octahedral) geometry around the Ni(II), Co(II) and Mn(II) ions due to the additional coordination from water. A supramolecular network is formed by extensive H-bonding in complex ( 1 ). The supramolecular assembly in complex ( 1 ) is additionally consolidated via the existence of unusual cyclic hexameric water clusters. The antimicrobial activities for the present complexes have been examined against Escherichia coli (K-12), Bacillus subtilis (MTC-121), Staphylococcus aureus (IOASA-22), Salmonella typhymurium (MTCC-98), Candida albicans, Aspergillus fumigatus and Penicillium marneffei . The superoxide dismutase (SOD) activity of the Cu(II) complex ( 1 ) is also assessed employing nitrobluetetrazolium (NBT) assay. [ABSTRACT FROM AUTHOR]