title: Structure determination of an intercalating ruthenium dipyridophenazine complex which kinks DNA by semiintercalation of a tetraazaphenanthrene ligand.
abstract: We describe a crystal structure, at atomic resolution (1.1 Å, 100 K), of a ruthenium polypyridyl complex bound to duplex DNA, in which one ligand acts as a wedge in the minor groove, resulting in the 51° kinking of the double helix. The complex cation Λ-[Ru(1,4,5,8-tetraazaphenanthrene)(2)(dipyridophenazine)](2+) crystallizes in a 11 ratio with the oligonucleotide d(TCGGCGCCGA) in the presence of barium ions. Each complex binds to one duplex by intercalation of the dipyridophenazine ligand and also by semiintercalation of one of the orthogonal tetraazaphenanthrene ligands into a second symmetrically equivalent duplex. The result is noncovalent cross-linking and marked kinking of DNA.
authors.affiliation: Department of Chemistry, University of Reading, Whiteknights, Reading RG6 6AD, United Kingdom.
authors.forename: James P
authors.initials: JP
authors.lastname: Hall
authors.forename: Kyra
authors.initials: K
authors.lastname: O'Sullivan
authors.forename: Abeer
authors.initials: A
authors.lastname: Naseer
authors.forename: Jayden A
authors.initials: JA
authors.lastname: Smith
authors.forename: John M
authors.initials: JM
authors.lastname: Kelly
authors.forename: Christine J
authors.initials: CJ
authors.lastname: Cardin
mesh_terms: D001372:Aza Compounds / Q000737:chemistry*; D003461:Crystallography; D004247:DNA / Q000737:chemistry*; D007364:Intercalating Agents / Q000737:chemistry*; D008958:Models, Molecular; D009690:Nucleic Acid Conformation; D009841:Oligonucleotides / Q000235:genetics; D009942:Organometallic Compounds / Q000737:chemistry*; D010616:Phenanthrenes / Q000737:chemistry*
chemical_list: D001372:Aza Compounds; D007364:Intercalating Agents; D009841:Oligonucleotides; D009942:Organometallic Compounds; D010616:Phenanthrenes; C483523:ruthenium dipyridophenazine; D004247:DNA