Search

Urease catalyzes the decomposition of urea into ammonia, which has harmful effects on both human health and fertile soil. Aiming at exploring novel urease inhibitors, a series of hydrazone compounds and their CoIII, CuII, NiII, and ZnII complexes were prepared from 4-methoxy-N'-(pyridin-2-ylmethylene)benzohydrazide (HL). They are [CoClL(NCS)] (1), [CoL2]·Cl·CH3OH·H2O (2), [CuL(NCNCN)]n·nCH3OH (3), [NiL(HL)]·ClO4·CH3OH (4) and [ZnClL(OH2)]·CH3OH (5). The compounds were characterized by physico-chemical methods. Structures of the complexes were further confirmed by single crystal X-ray diffraction. The metal ions in 1, 3, and 5 display square pyramidal coordination and 2 and 4 display octahedral coordination. The inhibitory effects of the compounds on Jack bean urease were evaluated. The results showed that 3 has effective urease inhibitory activity, with IC50 value of (7.3 ± 1.0) μmol L−1. [ABSTRACT FROM AUTHOR]

A series of metal(II) unsymmetrical Schiff-base complexes, {M(C10H6OCH:N(CH2)2N : C(CH3)CH : C(CH3)O), where M=Ni(II), Cu(II) and Zn(II)}, and their 2,2'-dipyridine (bipy) and 1,10-phenanthroline (phen) adducts are synthesized and characterized by microanalysis, magnetic susceptibility, conductance, IR and UV-Vis spectra. The ligand coordinates using the N2O2 chromophore to give a two-metal-center four-coordinate square-planar geometry. IR and UV-Vis spectra are consistent with octahedral adducts. The compounds are non-electrolytes in nitromethane and magnetic moments indicate that the complexes are magnetically dilute. The antimicrobial activity of the compounds against ten bacteria and one fungus are reported. The Cu(II) and Zn(II) complexes showed good activity against many of the organisms while their adducts are generally not sensitive. The minimum inhibitory concentrations (MICs) of the sensitive compounds are between 3.0-13.0 mg mL-1. [ABSTRACT FROM AUTHOR]