SYNTHESIS, CHARACTERIZATION, AND ANTITUMOR-ACTIVITY OF AMINE PLATINUM(II) AND PLATINUM(IV) TELLURATE COMPLEXES

A series of novel water-soluble amine platinum (II) tellurate complexe s of the type (A)Pt(II) [TeO2(OH)(4)], where A = 1,2-diaminocyclohexan e (DACH), 1,1-bis(aminomethyl)cyclohexane (AMCH), ethylenediamine (en) , or cyclopentylamine (cpa), were prepared either by the reaction of a mineplatinum (II) sulfate with barium tellurate or by a direct reactio n of (A)Pt(OH)(2) with telluric acid. Oxidation of the amine platinum( II) tellurate produced amine platinum(IV) tellurate (A)Pt(IV)trans(Z) [TeO2(OH)(4)] complexes, where Z = OH or Cl, following oxidation with hydrogen peroxide or with chlorine gas, respectively. Complexes were c haracterized by elemental analysis, and IR and Pt-195 NMR spectroscopy . Against i.p. murine leukemia cells in vivo, some of the complexes di splayed good antitumor activity when administered intraperitoneally (i .p.) on days 1, 5, and 9 at their optimal doses. Pt(II) complexes cont aining R,R-DACH, S,S-DACH, R,R-S,S-DACH, or AMCH produced %T/C of 147 to 288 whereas cis-DACH, en, and cpa complexes were inactive. In the P t(IV) series, the R,R-DACH complex with axial Cl was highly active (%T /C = 371, 40% cures) compared with the complex with axial OH (%T/C = 1 35).