Скачать или смотреть Enantiospecific Recognition of a DNA G‐Quadruplex by a Ruthenium Polypyridyl Complex

From Angew. Chem. Intern. Ed. Volume58, Issue29, July 15, 2019, Pages 9881-9885.
Structural Studies Reveal Enantiospecific Recognition of a DNA G‐Quadruplex by a Ruthenium Polypyridyl Complex
Kane McQuaid Holly Abell Dr. Sarah P. Gurung Dr. David R. Allan Dr. Graeme Winter Prof. Thomas Sorensen Prof. David J. Cardin Dr. John A. Brazier Prof. Christine J. Cardin Dr. James P. Hall
By using X‐ray crystallography, we show that the complexes Λ/Δ‐[Ru(TAP)2(11‐CN‐dppz)]2+ (TAP=1,4,5,8‐tetraazaphenanthrene, dppz=dipyridophenazine) bind DNA G‐quadruplex in an enantiospecific manner that parallels the specificity of these complexes with duplex DNA. The Λ complex crystallises with the normally parallel stranded d(TAGGGTTA) tetraplex to give the first such antiparallel strand assembly in which syn‐guanosine is adjacent to the complex at the 5′ end of the quadruplex core. SRCD measurements confirm that the same conformational switch occurs in solution. The Δ enantiomer, by contrast, is present in the structure but stacked at the ends of the assembly. In addition, we report the structure of Λ‐[Ru(phen)2(11‐CN‐dppz)]2+ bound to d(TCGGCGCCGA), a duplex‐forming sequence, and use both structural models to provide insight into the motif‐specific luminescence response of the isostructural phen analogue enantiomers.