Fairbanks, Simon D., Robertson, Craig C., Keene, F. Richard, Thomas, Jim A., and Williamson, Mike P. (2019) Structural investigation into the threading intercalation of a chiral dinuclear ruthenium(II) polypyridyl complex through a B‑DNA oligonucleotide. Journal of the American Chemical Society, 141 (11). pp. 4644-4652.

PDF (Published Version) - Published Version Restricted to Repository staff only

 

23

7

Abstract

Herein we report the separation of the three stereoisomers of the DNA light-switch compound [{Ru(bpy)2}2(tpphz)]4+ (tpphz = tetrapyrido[3,2-a:2',3'-c:3",2"-h:2‴,3‴-j]phenazine) by column chromatography and the characterization of each stereoisomer by X-ray crystallography. The interaction of these compounds with a DNA octanucleotide d(GCATATCG).d(CGATATGC) has been studied using NMR techniques. Selective deuteration of the bipyridyl rings was needed to provide sufficient spectral resolution to characterize structures. NMR-derived structures for these complexes show a threading intercalation binding mode with slow and chirality-dependent rates. This represents the first solution structure of an intercalated bis-ruthenium ligand. Intriguingly, we find that the binding site selectivity is dependent on the nature of the stereoisomer employed, with Λ RuII centers showing a better intercalation fit.

Actions (Repository Staff Only)

Item Control Page