Hypoxic Selective Agents-Synthesis Of Cobalt(Ⅲ) Complexes And Study On Their Bioactivity

Hypoxic phenomenon is a common character in tumor cells of human beings and animals. And oxygen pressure in most of people is lower than natural tissue of tumor origin. Hypoxia is one of environmental conditions which tumor development must go through. Its being is important on some sides, such as tumor development, malignant attack, distant transfer, and tumor resisting to radioactive therapy and chemical therapy. There are some evidences .in clinic and animal models that ensure hypoxic cell's existing in solid tumor. People take different measures to control the resisting to hypoxic cell in the therapy up to now, including adding radiosensitizer, using bioreductive agents, microwave therapy and so on.People take many steps to improve the tumor curative effect, but the results are not contented. Tumor therapist and researcher are applying themselves to look for a effective hypoxic toxic medicine or effective kill measures. In the 1990' s, professor Ware in New Zealand university find other ways and put forward new resolvent梙ypoxic-selective agents. The design principle is as following: Hypoxia-selective prodrugs can release diffusible cytotoxins on bioreduction in hypoxic regions. Such diffusible cytotoxins are required to be much more cytotoxic than the parent prodrug, to be sufffciently stable to allow them to diffuse from the hypoxic regions, and to be adequately, effective against all major tumor cell subpopulations.This paper selects cobalt as center atom and nitrogen mustard as bioactive ligands. In this paper, in order to study the structure characteristic of cobalt(III) complexes and find the new antitumor bioactivity, the work mention below were carried out:1.We have synthesized four secondary Ligands: Meacac, Etacac, Alacac, TAT, and four bioactive ligands: BCA.HCl, BBA.HBr, TCA.HC1, BCOA.2.We have synthesized nine complexes, six of which are not reported, such as Co (acac),NO1BBA, Co(Meacac).NO2BBA. .3.Their element analysis, infrared spectra and nuclear magnetic resonance hydrogen spectra were measured and structures of the ligands and complexes were determinded.4.We have evaluated the bioactivity of three complexes for the cleavage of PBR322 DNA. We can know Co(acac).NO2BBA is better than other complexes in the cleavage of DNA.