Complexes of N- and O-Donor Ligands as Potential Urease Inhibitors.

We report five new transition-metal complexes that inhibit the urease enzyme. Barbituric acid (), thiobarbituric acid (), isoniazid (), and nicotinamide () ligands were employed in complexation reactions. The resulting complexes were characterized using a variety of analytical techniques including infra-red and UV-vis spectroscopy, H NMR spectroscopy, elemental analysis, and single-crystal X-ray diffraction analysis. We describe two mononuclear complexes with a general formula {M()(HO)(HO)}, where M = Co () and Zn (), a mononuclear complex {Ni()(HO)(HO)} (), and two polymeric chains of a general formula {M() (HO)(HO)}, where M = Co () and Zn (). These complexes displayed significant urease enzyme inhibition with IC values in the range of 3.9-19.9 μM.