Complexes of Cadmium(II) and Mercury(II) with Cytidine 5'-Monophosphate and Diamines in Ternary Systems

摘要

Formation of Cd(II) and Hg(II) complexes in ternary systems with cytidine 5'-mono-phosphate (CMP) and diamines (en,tn,Put) has been studied.In Hg(II)/CMP/diamine systems the formation of heteroligand compounds is accompanied by the occurrence of non-covalent interactions and the formation of molecular complexes.The presence of polyamine in ternary systems does not change the metal-nucleotide mode of coordination.Similarly as in the binary Hg(II)/CMP system,the metallation involves the donor endocyclic nitrogen N(3) atom and CMP phosphate group.On the other hand,in the Cd(II)/CMP system,the introduction of a polyamine changes the coordination mode of the nucleotide.Phosphate group,inactive in binary systems,takes part in the complex-ation in ternary systems.In systems of cadmium(II) ions,CMP and diamines,only molecular complexes are formed,in which the polyamine is in the outer coordination sphere.In contrast to Cd(CMP)(H_2tn) and Cd(CMP)(H_2Put) compounds,in Cd(CMP)(H_2en) species the phosphate group of nucleotide does not take part in the metallation,i.e.the metal ion coordinates with CMP,through the atom N(3) of the nucleotide,and the phosphate group is involved in non-covalent interactions with en.