title: A comparative study of cytotoxicity and interaction with DNA/protein of five transition metal complexes with Schiff base ligands.
abstract: Five transition metal complexes NiL(1)2 (1), CuL(1)2 (2), ZnL(1)2 (3), [MnL(1)2(N3)]n·nCH2Cl2 (4), CuL(2)2 (5) {HL(1)=3-{[2-(2-hydroxy-ethoxy)-ethylimino]-methyl}-naphthalen-2-ol, HL(2)=2-{[2-(2-hydroxy-ethoxy)-ethylimino]-methyl}-phenol} have been synthesized and fully characterized. In all of the complexes, the ligands coordinated to the metal ion in a negative fashion via O and N donor atoms. The X-ray structures of nickel complex 1 and copper complexes 2 and 5 are four-coordinated monomers and show slightly distorted square-planar geometry in the vicinity of the central metal atom. Zinc complex 3 exhibits a four-coordinated tetrahedral structure. Differently, manganese complex 4 reveals a six-coordinated octahedral structure, one-dimensional chain is linked by azide in the end-to-end mode. In vitro cytotoxicity of these complexes to various tumor cell lines was assayed by the MTT method. The results showed that most of these metal-Schiff base complexes exhibited enhanced cytotoxicity than Schiff base ligands, which clearly implied a positive synergistic effect. Moreover, these complexes appeared to be selectively active against certain cell lines. The interactions of these metal complexes with CT-DNA were investigated by UV-vis, fluorescence and CD spectroscopy, the results indicated that these complexes are metallointercalators and can interact with CT-DNA. The study of interaction between complexes and BSA indicated that all of the complexes could quench the intrinsic fluorescence of BSA in a static quenching process.
authors.affiliation: Shandong Provincial Key Laboratory of Chemical Energy Storage and Novel Cell Technology, School of Chemistry and Chemical Engineering, Liaocheng University, Liaocheng 252059, China.
authors.forename: Meiju
authors.initials: M
authors.lastname: Niu
authors.affiliation: Shandong Provincial Key Laboratory of Chemical Energy Storage and Novel Cell Technology, School of Chemistry and Chemical Engineering, Liaocheng University, Liaocheng 252059, China. Electronic address: hongminlcu@163.com.
authors.forename: Min
authors.initials: M
authors.lastname: Hong
authors.affiliation: Shandong Provincial Key Laboratory of Chemical Energy Storage and Novel Cell Technology, School of Chemistry and Chemical Engineering, Liaocheng University, Liaocheng 252059, China.
authors.forename: Guoliang
authors.initials: G
authors.lastname: Chang
authors.affiliation: Shandong Provincial Key Laboratory of Chemical Energy Storage and Novel Cell Technology, School of Chemistry and Chemical Engineering, Liaocheng University, Liaocheng 252059, China.
authors.forename: Xiao
authors.initials: X
authors.lastname: Li
authors.affiliation: Shandong Provincial Key Laboratory of Chemical Energy Storage and Novel Cell Technology, School of Chemistry and Chemical Engineering, Liaocheng University, Liaocheng 252059, China.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Li
mesh_terms: D017209:Apoptosis / Q000187:drug effects; D001665:Binding Sites; D045744:Cell Line, Tumor; D002942:Circular Dichroism; D056831:Coordination Complexes / Q000737:chemistry* / Q000378:metabolism / Q000633:toxicity; D018360:Crystallography, X-Ray; D004247:DNA / Q000737:chemistry* / Q000378:metabolism; D045325:HCT116 Cells; D006801:Humans; D008024:Ligands; D008968:Molecular Conformation; D012545:Schiff Bases / Q000737:chemistry*; D013056:Spectrophotometry, Ultraviolet; D028561:Transition Elements / Q000737:chemistry* / Q000378:metabolism
chemical_list: D056831:Coordination Complexes; D008024:Ligands; D012545:Schiff Bases; D028561:Transition Elements; D004247:DNA