Syntheses, characterization, crystal structures and Jack bean urease inhibitory property of NiII, CdII, CuII and FeIII complexes with bis-Schiff bases

Four new nickel(II), cadmium(II), copper(II) and iron(III) complexes, [Ni3(L1)2(mu 2-eta 1:eta 1-CH3COO)2] (1), [Cd2(L1)2(CH3OH)2] (2), [Cu(L2)] (3) and [Fe2(L3)2(mu 2-OCH3)2] (4), where L1, L2 and L3 are the dianionic form of N,N'-bis(5-fluorosalicylidene)-1,3-propanediamine (H2L1), N,N'-bis(3,5-difluorosalicylidene)-1,3-propanedi-amine (H2L2) and N,N'-bis(4-fluorosalicylidene)-1,3-propanediamine (H2L3), respectively, were prepared. The compounds have been characterized by physico-chemical methods. The structures of the metal complexes were also confirmed by single crystal X-ray diffraction. The Ni atoms in complex 1 are in square pyramidal and octahedral coordination environments. The Cd atoms in complex 2 are in an octahedral coordination environ-ment. The Cu atom in complex 3 is in a tetrahedrally distorted square planar coordination environment. The Fe atoms in complex 4 are in an octahedral coordination environment. The Jack bean urease inhibitory assay indicated that the copper complex displays good activity.