Synthesis, Structures and Urease Inhibition Studies of Cobalt(II) and Copper(I) Complexes with Thiosemicarbazone Ligands

New cobalt(II) and copper(I) complexes, [CoCl 2 (L 1 ) 2 ] ( 1 ) and [CuClL 2 (Ph 3 P) 2 ]·CH 3 CN ( 2 ), where L 1  = 1-(4-bromobenzylidene)thiosemicarbazide, L 2  = 1-(2,4-dichlorobenzylidene)thiosemicarbazide, PPh 3  = = triphenylphosphine, were synthesized and characterized by elemental analysis and physico-chemical method, as well as single crystal X-ray diffraction. The complexes were also tested for their urease inhibitory properties. The cobalt complex has strong activity ( IC 50  = 5.7 μM). Enzymatic kinetics research suggested that the cobalt complex is a non-competitive urease inhibitor.