Premium
Design and DNA Binding of an Extended Triple‐Stranded Metallo‐supramolecular Cylinder
Author(s) -
Uerpmann Carsten,
Malina Jaroslav,
Pascu Mirela,
Clarkson Guy J.,
Moreno Virtudes,
Rodger Alison,
Grandas Anna,
Han Michael J.
Publication year - 2005
Publication title -
chemistry – a european journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.687
H-Index - 242
eISSN - 1521-3765
pISSN - 0947-6539
DOI - 10.1002/chem.200401054
Subject(s) - cylinder , supramolecular chemistry , diphenylmethane , ligand (biochemistry) , linear dichroism , crystallography , circular dichroism , dna , intercalation (chemistry) , chemistry , stereochemistry , materials science , geometry , crystal structure , receptor , organic chemistry , mathematics , catalysis , biochemistry
A new tetracationic triple‐stranded supramolecular cylinder is prepared from a bis(pyridylimine) ligand containing a diphenylmethane and two ketimine groups in the spacer. The cylinder is longer and slightly wider than the corresponding cylinder containing just diphenylmethane spacers. Inter‐strand CH⋅⋅⋅π interactions are not observed and this affects the relay of the chiral information within the cylinder; a mixture of rac and meso isomers results, with the meso isomer being the dominant solution species and characterised in the solid state by crystallography. This new cylinder does bind to DNA as confirmed by induced circular dichroism signals in both the metal‐to‐ligand charge transfer (MLCT) and in‐ligand bands of the cylinder. Flow linear dichroism demonstrates that the cylinder binds to DNA in a specific orientation(s) and is consistent with (major) groove‐binding as seen for the shorter cylinder. Some DNA bending/coiling is observed but the effect is much less dramatic than observed for the cylinder with diphenylmethane spacers confirming that coiling is not solely a consequence of the tetracationic charge, but rather is related to the precise size and shape of the cylinder.