Complexation in solution of magnesium(II) and cobalt(II) with purine 5′-monophosphates and pyrimide 5′-monophosphates: a potentiometric and calorimetric study

Abstract The interaction of Mg(II) and Co (II) with purine and pyrimidine nucleoside 5′-monophosphates was studied using potentiometric and calorimetric methods, with 0.1 M tetramethylammonium bromide as the background electrolyte at 25°. The presence in solution of the complexes [Mg(AMP) 2 ] 2 −, [Co(AMP) 2 ] 2 −, [Co(GMP) 2 ] 2 − [Co(IMP) 2 ] 2 − was observed. The relationship between enthalpies and the degree of macrochelation together with the stacking interaction between purine bases in the complexes are discussed.