Synthesis And Photoactivity Of DAMN Metal Complexes

As the second biggest death reason to people, cancer has threatened people's health seriously. Every year, there are about 7 million people died of cancer. Since cancer is very difficult to cure, and it is endangering people's life, it is becoming the main target in medicinal area. With the increasing knowledge of cancer and the development of science and technology, the skills for cancer therapy, such as surgical therapy, radiation therapy, anticancer chemical therapy, improved rapidly. But the current solutions for cancer therapy cannot meet people's demand. People now areStill striving to find the new methods for cancer therapy. Photodynamic therapy is one of the new important methods for cancer therapy.Photodynamic therapy (PDT) is a method by irradiating photosensitive compounds, which had been injected into a patient's body, with the given wavelength light it will produce singlet oxygen, which urge the putrescence of tumor tissue. The effect of PDT is relevant to the photosensitive compounds used. Different photosensitizes would have different effects. Recently people found that imines-Pt(II) complexes are benefit which can serve potentially in antitumour area.DAMN can coordinate either as a neutral ligand,forming complexes similar to those of ethylenediamine and related compounds,or as an anionic legend giving complexes analogous to those of o-phenylenediamine.But we have not seen the report relate to these complexes with DNA.On the basis of a number of literatures, we have synthesized a series of imines ligands, and imines-Pt(II)complexes, ascertain their rough structures by many ways;we have studied the interaction and reaction mechanism between complexes and DNA.Finally we selected the photosensitive complexes to investigate their photo- sensitivity. The work mention below were carried out:(1) We have synthesized three imines-Pt (II) complexes:[Pt (DAMN)2] ,Pt(OPDA)Cl2, Pt(Bipy)Cl2.We ascertained their rough structures with infrared spectra, nuclear magnetic resonance spectra, absorption spectra method, and elemental analysis.(2) We have synthesized three ligands using DAMN as the base, in addition we ascertained their rough structures with infrared spectra, nuclear magnetic resonance spectra, and elemental analysis.(3) By using absorption spectra method and EB as a fluorescence probe, we studied the action modes of the complexes binding to DNA.The results showed that complexe possibly bind to DNA by the modes of interaction and electrostatic binding. The Scatchard plots fit mixed model in which the K and n values both change, this means both competing and noncompeting modes exist. This indicates that complexe has two types of binding sites on DNA;that is to say, besides binding to the phosphate group, complexe can bind to DNA by intercalating to DNA duplex.(4) By using absorption spectra method, we studied the photoactivity of DAMN—Pt(II);The results showed that complexe would produce singlet oxygen with the given 630nm light. All of these results provide experimental bases for the further study on the antitumoractivity of the complexes.