Abstract
The interaction of the trimethyltin(IV) with some selected DNA constituents such as inosine, inosine 5′-monophosphate, adenine, adenosine, adenosine 5′-monophosphate, uracil, thymine, thymidine, cytosine and cytidine were investigated at 25°C and 0.1 M ionic strength in aqueous solutions and dioxane-water mixtures using potentiometry. The stepwise formation constants of the complexes formed in solution were calculated using the non-linear least-square program MINIQUAD-75. The concentration distribution of the various complex species was evaluated as a function of pH. The effect of dioxane as a solvent on the protonation constants of ligands and the formation constants of trimethyltin(IV) complexes were discussed. The thermodynamic parameters ΔH° and ΔS° calculated from the temperature dependence of the equilibrium constants were investigated.