Interaction of metal ions withe nucleic acids. Interaction of copper(II) with xanthosine and its derivatives

It was found that in the interaction of xanthosine with copper(II) nitrogen N-7, and not oxygen atoms of carbonyl groups, is involved. In aqueous solution of XMP, copper(II) interacts not only with N-7 and the phosphate group but also with ribose. In a crystalline copper(II)-XMP complex [Cu(C10H11O9N4P).H2O], only the phosphate group and N-7 are involved.