Synthesis, Characterization And Urease Inhibition Of Cu(II), Co(II), Ni(II), Mn(II) Complexes Of Schiff Base

The complexes, synthesized with transition metal and Schiff bases as reactants, are more and more becoming the focus of contemporary research. Owing to their various structures and peculiar properties, the use foreground of these complexes is also promising in many fields, such as catalysis, bioactivity and material. After going over and analyzing a great deal of the relevant literatures, we have synthesized 14 new transition metal complexes including 7 complexes of Schiff bases and studied their crystal structures and bioactivities. The following are the main work we have attained:1. Five Schiff base ligands have been designed and synthesized. They are derived from the condensation of salicylaldehyde and glycine,N-(2-aminoethyl)morpholine,4-(2-aminoethyl)phenylic acid,4-(2-aminoethyl)benzsulfamide and the condensation of 5-chlorosalicylaldehyde and 4-aminomethylfluobenzene, respectively. Seven complexes have been synthesized through the reaction of the Schiff base ligands and transition metal ions, such as Cu2+,Ni2+,Co2+,Mn2+. Their single-crystal complexes have been got via the advanced culture and their single-crystal structures have been got via the X-ray test. The mononuclear complexes are Cu(L1)(Py)(H2O),[Cu(L2)(Py)(H2O)](ClO-4)·H2O,Cu(L4) 2·2H2O,Ni(L4)2·2H2O,Ni(L5)2, (Py: pyridine) ; The dinuclear complexes are (CuL1)2·2/3(CH3OH),[Mn2(L5)2(N3)2](OCH3)2.2. The ligand HL6 of 2,5,8-triaza-1,9-di(2-fluorobenzyl-nonane) has been designed and synthesized, which is the reduced product of Schiff base ligand that is derived from the condensation of 2-fluobenzaldehyde and diethylenetriamine. Two complexes, [Cu(L5)(Cl-)](ClO-4) and Co(C18H20N3F2)(N3)3, have been synthesized through the reaction of the ligand and two transition metal ions Cu2+ and Co2+, respectively. The single-crystal complexes of two complexes have been got via the advanced culture and their structures have been got via the X-ray test. Both of them are the dinuclear compexes.3. Using six ligands (HL1,HL2,HL3,HL4,HL5,HL6) and their complexes as enzyme inhibitors, we have tested their inhibitory bioactivities against Urease and Xanthine Oxidase(XO). We find that none of these organic ligands exhibited ability to inhibit Urease and XO. On the contrary, nearly all the copper(II) complexes could inhibit the activities of Urease and XO. In addition, bioactivity of Urease could be inhibited by the complexes containing Ni2+,Mn2+ and Co2+, which failed to inhibit the bioactivity of XO. Herein we preliminarily study the connection between the molecular structures of these complexes and their inhibitory abilities against enzyme and deeply analyze the relationship between structure and property of the complexes which have inhibitory activity against Urease. What we have done will be helpful to study the matter which possesses inhibitory activity against Urease and find the excellent inhibitor against Urease.Besides, we have designed and synthesized five silver(I) complexes with 3-pyridine- carboxylic acid, 2-aminobenzoic acid 3,5-dinitrobenzoic acid, terephthalic acid, bi- phenyl-4,4'-di-carboxylic acid and 1,6-diaminohexane, 2-aminopyridine, 4-aminopyridine, 2-aminopyrimidine as raw materials. In the same way above, we have studied the relationship between the structures of these silver(I) complexes and their inhibitory activities of Urease, which deeply extends the research field of the matter which possesses inhibitory activity against Urease.