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The coumarilate (coum−) and 1,10-phenanthroline (phen) mixed ligand complexes of Co(II) (1), Ni(II) (2) Cu(II) (3) and Zn(II) (4) were synthesized and structural characterizations were performed by using elemental analysis, magnetic susceptibility, solid-state UV–Vis, FTIR spectra, thermoanalytical TG-DTG/DTA and single-crystal X-ray diffraction methods. The Co(II) and Ni(II) complexes are salt-type compounds, and they have two moles phen ligands bound as bidentate, two moles aqua ligands in coordination sphere and two moles anionic coum− ligand outside of the coordination unit as the counter-ion of the molecular structure. At the same time, the Co(II) and Ni(II) complexes have five moles of aqua ligands as hydrated water outside of the molecules. It was obtained that Cu(II) and Zn(II) complex structures contain one mole of phen ligand, two moles coordinated (coum−) ligand and a one-mole aqua ligand, and the molecules (Cu(II) and Zn(II)) have fivefold structure and obey square pyramidal geometry. Thermal decomposition of each complex started with dehydration (the first removal is the dehydration of complex Co(II) and Ni(II) as removal of hydrate–aqua molecules), and then, the decomposition of organic parts was observed. The thermal dehydration of the complexes takes place in one (Cu(II) and Zn(II)) or two (Co(II) and Co(II)) steps. The decomposition mechanism, thermal decomposition steps and thermal stability of the investigated complexes provide useful data for the interpretation of their structures. The final decomposition products were found to be metal oxides. Some biological applications (antifungal/antibacterial) were performed using structurally characterized compounds. [ABSTRACT FROM AUTHOR]

The complexes of metal cations with glycine amino acid were synthesized and characterized by FTIR, TGA, UV-Vis, and elemental analysis methods. Just the CuII-complex was suitably obtained as a single crystal. Neighboring chains are linked together to form a three-dimensional network via hydrogen-bonding interactions between coordinated water molecule, amino atoms, and O atoms of the bridging carboxylate groups. The other complex structures were thought to be similar to the CuIIstructure, and because of their spectroscopic studies they are similar to each other. Finally, the biological activities of complexes were investigated. The metal complexes showed more antimicrobial activity. The total antioxidant capacity of the metal complexes was determined. [ABSTRACT FROM AUTHOR]

Transition metal complexes of arginine (using Co(II), Ni(II), Cu(II) and Zn(II) cations separately) were synthesized and characterized by FTIR, TG/DTA-DrTG, UV-Vis spectroscopy and elemental analysis methods. Cu(II)-Arg complex crystals was found suitable for x-ray diffraction studies. It was contained, one mole CuII and Na+ ions, two arginate ligands, one coordinated aqua ligand and one solvent NO3− group in the asymmetric unit. The principle coordination sites of metal atom have been occupied by two N atoms of arginate ligands, two carboxylate O atoms, while the apical site was occupied by one O atom for CuII cation and two O atoms for CoII, NiII, ZnII atoms of aqua ligands. Although CuII ion adopts a square pyramidal geometry of the structure. CoII, NiII, ZnII cations have octahedral due to coordination number of these metals. Neighbouring chains were linked together to form a three-dimensional network via hydrogen-bonding between coordinated water molecule, amino atoms and O atoms of the bridging carboxylate groups. CuII complex was crystallized in the monoclinic space group P21, a = 8.4407(5) Å, b = 12.0976(5) Å, c = 10.2448(6) Å, V = 1041.03(10) Å3, Z = 2. Structures of the other metal complexes were similar to CuII complex, because of their spectroscopic studies have in agreement with each other. Copper complex has shown DNA like helix chain structure. Lastly, anti-bacterial, anti-microbial and anti-fungal biological activities of complexes were investigated. [ABSTRACT FROM AUTHOR]

Two new tetrahedral acesulfame complexes, acesulfamato(N)acesulfamato(O)bis(3-aminopyridine) zinc(II) (C 18 H 20 N 6 O 8 S 2 Zn, Zn-ace-3ap) and bis(acesulfamato-O)bis(benzotriazole)zinc(II) (C 20 H 18 N 8 O 8 S 2 Zn, Zn-ace-bta), were synthesized and characterized by single crystal X-ray diffraction, FT-IR spectroscopy, elemental analysis and thermal analysis techniques(TGA, DTA, DTG). The first compound, Zn-ace-3ap, crystallizes in triclinic space group P1 with parameters a = 7.978 (7) Å, b = 9.907 (6) Å, c = 15.778 (14) Å, α = 78.24° (2), β = 81.22° (4), γ = 75.99° (2), Z = 2 and The second compound, Zn-ace-bta, crystallizes in monoclinic space group C2/c with parameters a = 19.879 (3) Å, b = 9.3637 (13) Å, c = 14.0852 (18) Å, β = 105.483° (4), Z = 4. The biological activities of the synthesized complexes were appraised through disk diffusion method as antibacterial, antimicrobial and antifungal in DMSO. Enterococcus faecalis (ATCC-29212), Staphylococcus aureus (ATCC-25923) as gram-positive bacteria, Pseudomonas aeroginosa (ATCC-27853) and Escherichia coli (ATCC-25922) as gram-negative bacteria, and Candida albicans (ATCC-10231) as fungus were grown with a view to investigate the antimicrobial effects of the complexes. [ABSTRACT FROM AUTHOR]