The project is aimed at developing a theoretical background for systhesis and development of antitumor platinum and ruthenium drugs.The main goal is to evaluate the risk associated with mutagenic effects of novel platinum antitumor drugs. Mutagenic effects of new antitumor drugs woll be evaluated by Ames tests and with the aid of direct sequencing of DNA synthesized on templates containing sitespecifically placed platinum DNA adducts. Alterations in DNA conformation induced by the adducts of antitumor platinum drugs will be determined with aid of moderm methods of molecular biology and biophysics.These alterations will be to mutagenic efficiency of these drugs. The project will conrtibute to solving the problems of health care associated with the for new antitumor drugs,clarification of rheir side effects and safety.