Cancer is a major cause of death in Europe, being second to heart disease and responsible more than 1.7 million (6.7 worldwide) lives every year. It is expected that these numbers will rise dramatically such that by 2020 more than 16 million new cases will be registered, with the number of deaths more than 10.3 million people per year worldwide (in Europe the number of deaths is estimated to rise to at least 2 million per year). In recent years improved early diagnosis and treatment options have contributed significantly to the battle against cancer. Nevertheless, there are still many major tumors that cannot be treated and one of the major approaches to overcome this problem is to develop new active anticancer drugs. In this project, a promising approach to new polynuclear Ru-arene metal complexes based on the sugar phosphite moiety is described. The approach combines the highly effective polynuclear concept, established for Pt-anticancer complexes, with a new mode of action and transport provided by ruthenium-arene compounds. The polynuclear Ru-system should endow the compounds with improved cytotoxicity and the sugar component should provide high tumor-affinity (selective uptake into the tumor via the transferrin pathway and via upregulation of the glucalitic activity). In order to obtain a structure-activity relationship, a manifold of chemical characterization including structure elucidation, (bio)analytical studies on the binding to biological targets and in vitro assays are planned.