STUDY OF THE ACID-BASE BEHAVIOR AND COPPER(II) COMPLEXING PROPERTIES OF URACIL-DERIVED AND HYPOXANTHINE-DERIVED NUCLEOTIDES IN AQUEOUS-SOLUTION

A comparative study of the acid-base properties and the complex-formin g properties with copper(II) ions of the nucleotide uridine-5'-monopho sphate (UMP) and the cyclic nucleotides uridine-3',5'-cyclic-monophosp hate (cUMP) and inosine-3',5'-cyclic-monophosphate (cIMP) has been car ried out. This study was performed from emf and spectrophotometric dat a in aqueous solution at 37 degrees C and 0.15 M ionic strength, adjus ted either with NaNO3 or with NaCl. The pertinent equilibrium constant s were determined. The results show that purine derivatives are slight ly more acidic than the pyrimidine ones, and that nucleotides and cycl ic nucleotides coordinate with metal ions through different main coord ination sites.