| Schiff base and its complexes are widely used in the fields of biology, catalysis and material etc. Thus, studies on the synthesis of novel Schiff base complexes and their properties and application are significant the development of coordination chemistry.Deoxyribonucleic acid (DNA) is an important genetic substance in organism. As the basis of genetic expression, it plays an important role in the process of storing, copying and transmitting germ messages. Serving as a target molecule, the recognition of DNA for natural and artificial molecules in the inhibition of cellular disorders and in therapy of certain diseases is of paramount importance in inorganic biochemistry. The binding of small molecules, especially transition metal complexes, to DNA and molecular identification are very important in life science. It can provide useful information to design novel and efficient drugs for disease diagnosis and chemotherapeutic agents.Amino Acids is the basic unit of composition of the material for the study of amino acids and its derivatives is an important direction of development, as well as anti-cancer drugs with low toxicity and resistance, therefore it is a significant work for the study of amino acids. In this paper, three novel Schiff base ligands have been prepared, and seventy-eight coordination compounds of transition metal or lanthanide nitrates with these ligands have been synthesized. Some hetero atom-containing ligands such as 8-hydroxy quinoline, 1, 10-phenanthroline are also involved due to their planar configuration, which may be beneficial to their bioactivities. All these complexes are first reported. These ligands and complexes were characterized by elemental analysis, IR spectroscopy, UV spectroscopy, TG-DTG analysis and molar conductance analysis. The suggested structures of the complexes were concluded.(1) The compositions of the complexes with Schiff base ligands from glycine- 2-hydroxy-1-naphthaldehyde are confirmed to be[M(GNA)(H2O)]·nH2O(M=Cu(Ⅱ),Mn(Ⅱ),Cd(Ⅱ), n=1; M=Ni (Ⅱ), n=2; M=Co(Ⅱ), n=3); [M(GNA)L1]·nH2O(M= Cu(Ⅱ),Cd(Ⅱ),n=2; M=Mn(Ⅱ),Co(Ⅱ), n=3; M= Ni(Ⅱ),n=4); [M(GNA) L2]·n H2O(M=Cu(Ⅱ),Cd(Ⅱ), Mn(Ⅱ),Co(Ⅱ) , n=2; M=Ni(Ⅱ),n=3); [Ln(GNA) (NO3)2]·nH2O( Ln=La(Ⅲ),Gd(Ⅲ),Sm(Ⅲ) ,n=1;Ln= Yb(Ⅲ), n=2; Ln=Dy(Ⅲ), n=3); [Ln(GNA)L1(NO3)]·nH2O (Ln=La(Ⅲ),Gd(Ⅲ),Sm(Ⅲ),Yb(Ⅲ),Dy(Ⅲ) , n=2) ; [Ln(GNA)L2(NO3)]·nH2O (Ln=La(Ⅲ),Gd(Ⅲ),Sm(Ⅲ),Yb(Ⅲ),Dy(Ⅲ) , n=2) , respectively.(2) The compositions of the complexes with Schiff base ligands from glycine- 2,4-dihydroxybenzaldehyde are confirmed to be[M2(GDH)2]·nH2O (M=Cu(Ⅱ),Co(Ⅱ) ,n=2;Ni(Ⅱ) ,n=1) ; [(GDH)2L1M2]·nH2O(M=Cu(Ⅱ), n=1; M=Co(Ⅱ),Ni(Ⅱ), n=3) ; [M2(GDH)2 L2]·nH2O (M=Cu(Ⅱ),Ni(Ⅱ),n=2 ;M= Co(Ⅱ),n=4) ; [Ln2 (GDH)2 (NO3)4]·nH2O(Ln=La(Ⅲ),Gd(Ⅲ),Sm(Ⅲ) , Yb(Ⅲ), Dy(Ⅲ), n=2); [Ln 2 (GDH)2L1 (NO3)2]·2H2O(Ln=La(Ⅲ),Gd(Ⅲ),Sm(Ⅲ) , Yb(Ⅲ), Dy(Ⅲ), n=2); [Ln 2 (GDH)2L2 (NO3)2]·2H2O(Ln=La(Ⅲ),Gd(Ⅲ),Sm(Ⅲ) , Yb(Ⅲ), Dy(Ⅲ), n=2), respectively.(3) The compositions of the complexes with Schiff base ligands from glycine-o-vanillin are confirmed to [M(GOV)(H2O)]·nH2O(M=Cu(Ⅱ),Ni(Ⅱ),n=3; M=Co(Ⅱ),n=4) ; [M (GOV)L1]·nH2O (M =Cu(Ⅱ), n=3; M=Co(Ⅱ),Ni(Ⅱ),n=2) ; [M(GOV)L2]·nH2O (M=Cu(Ⅱ),n=3; M=Co (Ⅱ),Ni(Ⅱ),n=2); [Ln(GOV)(NO3)2] (NO3)·nH2O (Ln=La(Ⅲ), n=2; Ln=Dy(Ⅲ),Sm (Ⅲ), n=3;Ln=Yb(Ⅲ),Gd(Ⅲ),n=4); [Ln(GOV) L1 (NO3)](NO3)·nH2O(Ln=La(Ⅲ), n=2; Ln=Dy(Ⅲ),Sm(Ⅲ), n=3; Ln= Yb(Ⅲ),Gd(Ⅲ) ,n=4); [Ln(GOV)L2(NO3)](NO3)·nH2O (Ln=La(Ⅲ),,Sm(Ⅲ),Yb(Ⅲ),Dy(Ⅲ), n=3; Ln= Gd(Ⅲ), n=4) , respectively.All of the ligands and complexes were prepared in non-aqueous solvents under moderate conditions. In the complexes, the nitrogen atom of Schiff base , oxygen atom of hydroxybenzene and the oxygen atom in carboxylic acid are all coordinated to the metal ions .Water molecules are coordinated to the acceptor or exists as crystal water. The nitrate ions are within the coordination sphere or outer of it, those within it are coordinated to the metal ions in the form of bidentate. Combinating Achar differential and Coats-Redfern integral method which fits the thirty kinetic equations, the calculating program of thermal decomposition for complexes was designed. The kinetic equations of corresponding kinetic parameters were obtained. The kinetic parameters include E, A, order of reaction and correlation coefficient etc. The activation entropyΔS ≠and activation free-energyΔG ≠for some thermal decomposition steps were also calculated.The thermal decomposition kinetic function of [Cu(GNA)(H2O)]·H2O in step(1) may be expressed as f (α) = 1/4(1 -α)[ - In(1 -α)]-3,the kinetic equation of thermal decomposition may be expressed as dα/dt = Ae - E / RTi1 / 4(1 -α)[ - In(1 -α)]-3, E= 224.63 kJ/mol,InA=69.31;ΔS ≠=327.03J/mol·K,ΔG ≠=104.61kJ/mol,and those in step(3) are: f (α) = 3/ 2[(1 -α)-1/3 - 1]-1, dαdt = Ae-E/RTi3 / 2[(1 -α)-1/3-1]-1,E =542.81 kJ/mol,InA=106.54;ΔS ≠=327.03J/mol·K,ΔG ≠=102.21kJ/mol.Data of TG-DTG analysis of other complexes including [Cu(GNA)L1]·2H2O,[Cu(GNA)L2]·2H2O,[La(GNA)(NO3)2]·H2O,[(GDH)2Cu2]·2H2O,[La2(GDH)2 (NO3)2]·2H2O,[Dy2(GDH)2 (NO3)2]·2H2O,[La(GOV)L2(NO3)](NO3)·3H2O,[La(GOV)L2(NO3)] (NO3)·3H2O,[Sm(GOV) (NO3)2] (NO3)·3H2O are omitted.In this paper, reaction conditions, interaction modes, binding ratios and binding constants between metal complexes and deoxyribonucleic acid (DNA) have been determined by means of electrochemical and spectroscopic methods.The interaction between metal complex of [Cu (GNA) (H2O)]·H2O and DNA has been studied by means of electrochemical methods. The interaction mode of [Cu(GNA)H2O]·H2O to deoxyribonucleic acid is electrostatic force, the bind constant is 1.67×104 L·mol-1. The interaction modes of [Cu(GNA)L1]·2H2O,[Cu(GNA) L2]·H2O,[Cu2(GDH)2]·2H2O,[Cu2(GDH)2L1]·H2O,[Cu2(GDH)2 L2]·2H2O,[La(GOV) (NO3)2] (NO3)·2H2O,[La(GOV)L1 (NO3)] (NO3)·3H2O and [La(GOV)L2 (NO3)] (NO3)·3H2O to deoxyribonucleic acid are intercalation and binding constants are 4.6×102,6.05×104,0.63×104,1.15×104,1.47×104,3.42×103,2.65×104 and 1.13×105 L·mol-1, respectively. The binding ratios and binding constants are related to the planar and flat area of the complexes. It has been demonstrated the more co-planar of complexes exist covalent bond. It was in good agreement with electrochemical conclusions that the property of DNA interacting the complexes was discussed by UV spectra and fluorescence spectra.Antibacterial circle distribution measurement was used to determine the antibacterial activity of some complexes, respectively. Experiments indicate that the antibacterial activity was positively correlated with concentration and the complex should generally have a higher antibacterial activity than ligand.
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