STRUCTURES OF 2 N(1)-BOUND PLATINUM(II)-6-OXOPURINE COMPLEXES - COMPARISONS WITH COMPLEXES DERIVED FROM PLATINUM(II) ANTI-TUMOR AGENTS

The preparation and molecular structure of [(diethylenetriamine) (7,9-dimethylhypoxanthine) platinum(II)] (PF6)2·1.5H2O and [(ethylenediamine) (7,9-dimethylhypoxanthine)2platinum(II)] (PF6)2, are reported. These complexes represent the first structurally characterized N(1)-bound Pt(II) 6-oxopurine complexes. In each case, the Pt(II)N(1) bond length [2.051(6)A in the diethylenetriamine complex and 2.021(8)A in the ethylenediamine complex] indicates a strong metal-to-base binding. Both complexes contain interligand hydrogen bonds, with the ammine ligand acting as the donor and the O(6) atom of the base acting as the acceptor. These N(1)-bound complexes are compared with N(7)-bound 6-oxopurine and N(3)-bound cytosine complexes of Pt(II) anti-tumor agents. © 1979.