Abstract
The platinum complexes of diaminocarboxylates (charged complexes) and their ethyl ester derivatives (non-charged complexes) were prepared and examined for antitumor activity. The non-charged complexes are antitumor-active, while the charged complexes are inactive. The interaction of deoxyribonucleic acid (DNA) with the charged and non-charged complexes was examined by means of ultraviolet (UV) difference spectroscopy. Since the UV difference spectral patterns obtained in this work were almost the same, the binding mode of the charged complexes to DNA seems to be the same as that of the non-charged complexes. However, the presence of negative charge lowers the reactivity of the platinum complexes with DNA. The antitumor-inactivity of the charged complexes may be due to a combination of their reduced ability to permeate into cells and the lower reactivity with DNA.
