Thread Insertion of a Bis(dipyridophenazine) Diruthenium Complex into the DNA Double Helix by the Extrusion of AT Base Pairs and Cross-Linking of DNA Duplexes

摘要

The crystal structure of the Δ,Δ enantiomer of the binuclear "light-switch" ruthenium complex [μ-(11,11-bidppz)(l,10-phenanthroline)4Ru2]~(4+) bound to the oligonucleotide d(CGTACG) shows that one dppz moiety of the dumbbell-like compound inserts into the DNA stack through the extrusion of an AT base pair. The second dppz moiety recruits a neighboring DNA molecule, and the complex thus cross-links two adjacent duplexes by bridging their major grooves.