Equilibrium, kinetic and HPLC study of the reactions between platinum(ii) complexes and DNA constituents in the presence and absence of glutathione

摘要: The complex formation equilibria of [Pt(SMC)(H2O)2]+ and [Pt(terpy)H2O]2+, where SMC = S-methyl-L-cysteine terpy = 2,2′:6′,2″-terpyridine, with some biologically relevant ligands such as inosine (INO), inosine-5′-monophosphate (5′-IMP), guanosine-5′-monophosphate (5′-GMP) glutathione (GSH) were studied. stoichiometry stability constants the complexes formed are reported, concentration distribution various species have been evaluated a function pH. Also kinetics mechanism reactions studied nucleophile temperature. For [Pt(SMC)(H2O)2]+, two consecutive reaction steps, which both depend on concentration, observed under all conditions. negative entropies activation support an associative mechanism. Reaction Pt(II) was carried out in presence absence at neutral rate clearly showed kinetic preference toward GSH also monitored by HPLC. However, only small amount coordinated 5′-GMP detected HPLC trace. products isolated characterized MALDI-TOF mass spectrometry.