Enantiospecific formation of a metal-mediated base pair inside a DNA duplex
Biswarup Jash, Johannes Neugebauer, Jens Müller
Inorganica Chimica Acta
The metal-mediated base pair P–Ag(I)–P involving the bidentate ligand 1H-imidazo[4,5-f][1,10]phenanthroline (P) was investigated within a B-DNA duplex. The underlying tetrahedral complex exists as a pair of enantiomers. Interestingly, one of the isomers forms preferentially within the B-DNA context, as was shown in a combined computational and experimental approach by means of circular dichroism spectroscopy. Towards this end, the homoleptic Ag(I) complexes of 1-methyl-1H-imidazo[4,5-f][1,10]phenanthroline and both enantiomers of 3-(1H-imidazo[4,5-f][1,10]phenanthrolin-1-yl)propane-1,2-diol were investigated outside the DNA context as well as the P–Ag(I)–P base pair within the DNA context. In this paper, we also propose a simplified nomenclature for the enantiomers of undistorted tetrahedral complexes bearing asymmetric bidentate ligands.
Circular dichroism, Stereochemistry, Inorganic chemistry, Biochemistry