The Structure Of Cadmium (?), Nickel (?) And Cobalt (?) Coordination Polymers Of 5-(1-pyrazole) Nicotinic Acid With Anti-tumor Activity

In 1893,the theory of coordination chemistry was founded by the Swedish chemist Michel Werner?A.werner?.Since then,coordination chemistry has been the focus of inorganic chemistry research and has attracted the attention of researchers.In recent decades,the structure and biological properties of inorganic or organic materials are significant in the fields of chemistry and biological sciences.In the field of coordination chemistry,the groups of ligands largely determined the properties of ligands.Nitrogen-containing heterocyclic ligands contain N atoms with strong coordination ability.Carboxylic acid ligands containing O atoms also have strong coordination ability.So this kind of ligand has drawn much attention.In the process of complex synthesis,ligand and central ion form a series of complexes with coordination bond.In addition,the ligands between the ligands and free water can form a one-dimensional chain,two-dimensional layer and three-dimensional network structure pass?-?stacking,hydrogen bonds and other weak interactions.Transition metal is an essential trace element of human body,and DNA plays a crucial role in the genetics of life.Therefore,the ways and mechanisms of the interaction between transition metal complexes and DNA are explored.In order to explore the potential applications of the complexes in antitumor drugs,molecular biology and its related fields of application has very important significance.The main research in this paper includes five sections as follows:1.Complexes 1-4 were synthesized by hydrothermal method.As follows:complex 1:Cd₂L₂?H₂O?₂Cl₂;complex 2:Ni₂L₂?H₂O?₄;complex 3:Co₂L₂?H₂O?₄;complex 4:Cd₂L₂?H₂O?₂;L=5-?pyrazol-1-yl?nicotinic acid2.Complexes 1-4 were characterized and verified by IR,elemental analysis and single-crystal X-ray crystallography.All of them were hexa-coordinated.Complex 1?2?3 are monoclinic,and complex 4 is triclinic.3.The binding behavior to DNA were studied by means of fluorescence spectrum and UV/Vis spectrum.The results show that there was strong interaction between complexes and DNA.The fluorescence quenching constants K_sq of complexes 1-4 are:complex 1:0.2332;complex 2:0.1867;complex 3:0.1589;complex 4:0.1410.The result showed that complexes and DNA are mainly based on the mode of insertion.4.Gel-electrophoresis method was used for determination of four complexes to cleave pBR322 DNA.Complex 1 was the better one.5.Apoptosis assay detected by flow cytometry showed the complexes can induce apoptosis of the HeLa human tumor cells.Within a certain time range,the longer the time,the more obvious apoptosis.