Electrochemical evaluation of rhodium dimer-DNA interactions.

The interaction of rhodium dimers, including the carboxylates (acetate, propionate, butyrate, trifluoroacetate, citrate and gluconate), amidates (acetamidate and trifluoroacetamidate) and carboxamidate (Doyle catalyst S) with DNA was investigated by electrochemical methods. Differential pulse voltammetry measurements showed, in agreement to literature data, that most of rhodium carboxylates have a higher affinity for adenine than guanine residues. Some differences of reactivity may be correlated with the compound structures and these were helpful in understanding the influence of equatorial ligands on axial coordination mechanisms. The preliminary results might be extended for further studies on quantitative structure activity relationship approaches, highlighting electrochemical methods as a tool for this purpose.