Syntheses and Antitumor Activities of 1R, 2R-Cyclohexanediamine Pt (II) Complexes Containing Dicarboxylates

Abstract

New 1R, 2R-cyclohexanediamine (=1R, 2R-dach) Pt (II) complexes containing dicarboxylate ions, i.e., ketomalonate, malate, saccharate, glutarate, diphenate, and α, β-diphenylsuccinate were synthesized and tested against leukemia L1210 in vivo. All of the dicarboxylato Pt (II) complexes showed relatively high antitumor activities with T/C% values of more than 200 at optimal doses. In particular, mucato and α, β-diphenylsuccinato Pt (II) complexes exhibited excellent antitumor activities with T/C% values of 348 and 369, respectively, with 3 cured mice out of six.
The dicarboxylato Pt (II) complexes were determined by elemental analyses to contain dicarboxylates : Pt : 1R, 2R-dach in a ratio of 1 : 1 : 1. The molecular secondary ion mass spectra of saccharato and glutarato Pt (II) complexes indicate that these complexes exist in a binuclear form together with a mononuclear form in aqueous solution.