Tautomeric structures, nucleobase-metal

Examples of three metal ions binding simultaneously to a neutral nucleobase in its preferred tautomeric structure are scarce. One example, with Pt(II) at N7 of 9-MeA and Ag+ at N1 and N3 (132), gives rise to a helical polymer in the solid state. The effect of the three metal ions on the acidity of the exocyclic amino group has not been determined. 

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