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Updated: May 20, 2026

In Vitro Chemical Mapping of G-Quadruplex DNA Structures by Bis-3-Chloropiperidines
Published on: May 12, 2023
Photoisomerizable arylstilbazolium ligands recognize parallel and antiparallel structures of G-quadruplexes
Izabella Czerwinska1, Bernard Juskowiak
1Faculty of Chemistry, Adam Mickiewicz University, Grunwaldzka 6, 60-780 Poznan, Poland.
Abstract:
The photoisomerization and DNA interaction studies of three arylstilbazolium derivatives with various samples of nucleic acids (duplexes, triplexes and tetraplexes) are reported. The equilibrium dialysis study revealed high binding affinities of ligands to tetraplex structures. The quadruplex-binding affinity could be switched by light, e.g., the E,E and E,Z isomers of 1,4-bis(vinylquinolinium)benzene (1) interacted with parallel and antiparallel tetraplexes exhibiting different binding selectivity. The E,Z-1 showed higher binding preference for c-myc DNA (a propeller-type quadruplex), whereas the E,E-1 favorably interacted with telomeric DNA (a basket-type quadruplex). The presence of quadruplex DNA hampered photoisomerization of quadruplex-bound ligand.
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