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A series of homo-, heterodinuclear and homotrinuclear copper(II) complexes containing a new Schiff base ligand and 1,10-phenanthroline were synthesized. Based on results of elemental analyses, FTIR, 1 H-and 13 C-NMR spectra, conductivity measurements and magnetic susceptibility measurements, the complexes had general compositions {[Cu(L)(H 2 O)M(phen) 2 ](ClO 4 ) 2 [M = Cu(II), Mn(II), Co(II)]} and {[Cu 3 (L) 2 (H 2 O) 2 ](ClO 4 ) 2 }. The metal : L : phen ratio is 2 : 1 : 2 for the dinuclear copper(II) complexes and the metal : L ratio was 3 : 2 for the trinuclear copper(II) complex. The liquid-liquid extraction of various transition metal cations [Mn(II), Co(II), Ni(II), Cu(II), Zn(II), Pb(II), Cd(II), Hg(II)] from the aqueous phase to the organic phase was carried out using the diimine-dioxime ligand. It was concluded that the ligand can effectively be used in solvent extraction of copper(II) from the aqueous phase to the organic phase. Furthermore, catalytic activitiy of the complexes for the disproportionation of hydrogen peroxide was also investigated in the presence of imidazole. Dinuclear copper(II)-manganese(II) complex has some similarity to manganese catalase in structure and activity. The interaction between these complexes and DNA has also been investigated by agarose gel electrophoresis; we found that the homo-and heterodinuclear copper complexes can cleave supercoiled pBR322 DNA to nicked and linear forms in the presence of H 2 O 2 .

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A new series of homo-and heteropolynuclear copper(II) complexes of N,N″-bis[1-biphenyl-2-hydroxyimino-2-(4-acetylanilino)-1-ethylidene]-diamines have been prepared and characterized by different physical techniques. The starting point of the research was the reaction of chloroacetyl chloride with biphenyl in the presence of aluminum chloride. 4-Biphenylhydroximoyl chloride was obtained by reacting synthesized 4-(chloroacetyl)biphenyl with alkyl nitrite. Substituted 4-(alkylaminoisonitrosoacetyl)biphenyl (ketooxime) was prepared by reacting 4-biphenylhydroximoyl chloride with 4-aminoacetophenone in EtOH. Homodi-, homotrinuclear and heterodinuclear copper(II) perchlorate complexes of tetradentate Schiff bases which possess N 4 donor sets derived from the condensation of 4-(arylaminoisonitrosoacetyl)biphenyl and diamine derivatives were synthesized and characterized. Elemental analysis, FT-IR, ESR, molar conductivity, magnetic moment measurements and thermal analyses studies were utilized for the investigation of the complexes. The free ligands were also characterized by 1 H-and 13 C-NMR spectra. Elemental analyses, stoichiometric and spectroscopic data of the metal complexes indicated that the metal:ligand ratio of dinuclear copper(II) complexes were found to be 2 : 1 while this ratio was 3 : 2 in trinuclear copper(II) complexes and the metal complexes indicated that the metal ions are coordinated to the oxime and imine nitrogen atoms. The extraction abilities of the novel ligands were also evaluated in chloroform by using several transition metal picrates such as Mn 2+ , Co 2+ , Ni 2+ , Cu 2+ , Zn 2+ , Pb 2+ , Cd 2+ , Hg 2+ . It has been observed that both ligands show a high affinity to Cu 2+ ions.

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Hepatocellular carcinoma is one of the most prevalent cancers, with a high morbidity rate, even in developed countries. In the present study, the curative effect of the Schiff base (SB) heterodinuclear copper(II)Mn(II) complex on diethylnitrosamine (DEN)-induced liver carcinoma was investigated. Hepatocarcinoma was initiated by an injection of DEN and promoted by phenobarbital (0.05%) in the diet. In addition, the potential nephrotoxicity of SB was evaluated in a cisplatin-induced nephrotoxicity model. Rats were administered the SB complex (1 and 2 mg/kg body weight/day) for 24 weeks, and cancer progression was investigated by macroscopic, histopathological, and western blot examinations. The administration of SB decreased the incidence and the number of hepatic nodules in a dose-dependent manner by regulating inflammation response and the apoptotic pathway. Western blot analyses from the livers of rats treated with SB after DEN induction showed significantly enhanced Bax and caspase-3 levels, with a marked decrease in the levels of Bcl-2, NF-κB p65 and cyclooxygenase (COX)-2. Results from the nephrotoxicity study showed that, whereas cisplatin increased serum urea nitrogen and creatinine levels, no increase in serum biochemical parameters was detected in SB-treated animals. Moreover, protein levels of NF-E2-related factor-2 (Nrf2) and heme oxygenase-1 were lower, whereas nuclear factor-κB (NF-κB p65) and activator protein-1 levels were higher in the kidneys of cisplatin-treated animals compared with that of the SB groups. Therefore, the SB complex could be an alternative chemotherapeutic option for liver cancer treatment once its safety in clinical applications has been examined.