Preparation and antitumor evaluation of water-soluble derivatives of dichloro(1,2-diaminocyclohexane)platinum(II).

The structure of the antitumor agent, dichloro(1,2-diaminocyclohexane)platinum(II) (NSC-194814), was modified by replacing the chlorides with organic or inorganic anions. Eighteen new platinum complexes were so isolated and their antitumor properties against the L1210 leukemia in C57BL/6 X DBA/2 mice were evaluated. Most of the complexes were readily soluble in water and some had enhanced antitumor activity compared to the parent dichloro complex. In addition, increased solubility with retention of significant antitumor activity was obtained by oxidizing the parent dichloroplatinum(II) complex with halogen or peroxide to give two platinum(IV) complexes. Some previously reported platinum complexes with phosphorus, selenium, or tellurium electron donor ligands were also synthesized and assessed for antitumor action, but these did not show appreciable activity.