@article{3067506,
    title = "Synthesis, characterization and crystal structure of novel mononuclear peroxotungsten(VI) complexes. Insulinomimetic activity of W(VI) and Nb(V) peroxo complexes",
    author = "Maniatakou, A. and Karaliota, S. and Mavri, M. and Raptopoulou, C. and Terzis, A. and Karaliota, A.",
    journal = "Journal of Inorganic Biochemistry",
    year = "2009",
    volume = "103",
    number = "5",
    pages = "859-868",
    issn = "0162-0134",
    doi = "10.1016/j.jinorgbio.2009.03.001",
    keywords = "adrenalin;  carboxylic acid derivative;  counterion;  fatty acid;  hydrogen;  insulin;  metal derivative;  peroxoniobium complex;  peroxotungsten complex;  quinaldic acid;  quinoline derivative;  tungsten derivative;  unclassified drug, adipocyte;  animal cell;  article;  controlled study;  crystal structure;  drug effect;  drug structure;  drug synthesis;  hydrogen bond;  in vitro study;  infrared spectroscopy;  inhibition kinetics;  insulin like activity;  insulinomimetic activity;  ligand binding;  nonhuman;  proton nuclear magnetic resonance;  Raman spectrometry;  rat;  X ray diffraction, Adipocytes;  Animals;  Cells, Cultured;  Crystallography, X-Ray;  Fatty Acids, Nonesterified;  Insulin;  Magnetic Resonance Spectroscopy;  Niobium;  Organometallic Compounds;  Quinolines;  Rats;  Spectrum Analysis, Raman;  Tungsten Compounds",
    abstract = "Two new mononuclear peroxo complexes of tungsten of the formula (gu)2[WO2(O2)2] (1) and (gu)[WO(O2)2(quin-2-c)] (2a) (where gu+ = guanidinium ion, CN3 H6+ and quin-2-c = quinoline-2-carboxylate ion) have been synthesized and characterized by elemental analysis, infrared, Raman, UV-visible and 1H NMR spectroscopies. The crystal structure of (gu)[WO(O2)2(quin-2-c)] · H2O (2b) determined by X-ray diffraction indicates that the side-on peroxo groups and the bidentate quinaldate ligand bind the W(VI) centre leading to an hepta coordination mode. The guanidinium ion occurring as a counterion and the hydrogen-bound interactions stabilize the complexes. The in vitro insulin-mimetic effect of the complexes has been evaluated by the inhibitory effect on free fatty acid release in isolated fat adipocytes treated with epinephrine. Moreover the niobate analogues, synthesized and characterized previously, (gu)3[Nb(O2)4] and (gu)2[Nb(O2)3(quin-2-c)] · H2O have been tested for the insulin-like activity. © 2009 Elsevier Inc. All rights reserved."
}