Platinum(IV) Complexes with Cytosine and Threonine

The systems Pt(IV)-cytosine-water and Pt(IV)-threonine-water with a 1 : 2 reagent ratio and the Pt(IV)-cytosine-threonine-water (1 : 1 : 1) system were studied by potentiometry. The formation constants of complexes logβ were determined to be 18.7 (Cyt), 10.21 (Thr), and 16.8 (Cyt-Thr). The occurrence of the organic ligands coordinated with Pt(IV) and their coordination modes were established by IR spectroscopy (400-4000 cm-1) and 1H, 13C, and 195Pt NMR.