Interaction of dimethyltin(IV)dichloride with 5′-AMP and 5′-GMP

Abstract

The formation constants of the species formed in the systems H+ + dimethyltin(IV) + 5′-AMP and 5′-GMP, H+ + 5′-AMP, and H+ + 5′-GMP have been determined in aqueous solution in the pH range of 1.5–9 at constant temperature (25 °C) and constant ionic strength (0.1 mol dm–3, NaClO4) using spectrophotometric and potentiometric techniques. 1H and 31P NMR investigations in aqueous solution confirmed the species formation and led us to propose their structures. The precipitated complexes of AMP and GMP by Me2Sn(IV)2+ at low pH values were characterized by elemental analysis and FTIR spectroscopy, which ruled out purine moiety (N-1 and N-7) coordination and a bidentated coordination of the phosphate group is concluded in both cases.Key words: dimethyltin(IV)dichloride, guanosine 5′-monophosphate, adenosine 5′-monophosphate, stability and protonation constants.