Synthesis and antitumor activity of 1,2-diaminocyclohexane platinum(IV) complexes

The synthesis, characterization, and antitumor activity of a series of platinum(IV) complexes of the type DACH-PtIV(X)2Y (where DACH = trans-dl, or trans-l-1,2-diaminocyclohexane, X = OH or Cl, and Y = oxalato, malonato, methylmalonato, tartronato, ketomalonato, 1,1-cyclopropanedicarboxylato, or 1,1-cyclobutanedicarboxylato, are described. These complexes have been characterized by elemental analysis, HPLC, and infrared and 195Pt NMR spectroscopic techniques. The complexes had good in vitro cytotoxic activity (IC50 = 0.14-7.6 micrograms/ml) and were highly active in vivo against leukemia L1210 cells (%T/C = 152- > 600, cisplatin = 218). In addition, excellent in vivo antitumor activities against B16 melanoma (%T/C = 309), M5076 reticulosarcoma (100% cures) and cisplatin-resistant L1210/DDP (%T/C = 217) cell lines were also exhibited by an analog selected for further evaluation.