Introduction of axial chirality in a planar aromatic ligand results in chiral recognition with DNA

Dimerization of a hydroxycarbazole produces an axially chiral biaryl, BICOL ( 2 ). One enantiomer (R)‐ 2 , is capable of enantioselective binding to different polymorphs of DNA. The biaryl (R)‐ 2 was shown by fluorescence and circular dichroism to induce a shift of Z‐DNA to B‐DNA. The opposite enantiomer (S)‐ 2 shows no specific binding. The significant difference in behaviour between the two enantiomers (S)‐ 2 and (R)‐ 2 is in line with molecular modelling studies which show two very different binding geometries between the enantiomers with each polymorph of DNA. Copyright © 2010 John Wiley & Sons, Ltd.