Facile syntheses of disubstituted bis(vinylquinolinium)benzene derivatives as G-quadruplex DNA binders

A series of disubstituted bis(vinylquinolinium)benzene derivatives were designed, which were prepared through a facile three-component one-pot reaction in good yield. FRET results showed that 1,3-disubstituted benzene derivatives had much stronger stabilization effect on G-quadruplex DNA than that of 1,4-disubstituted benzene derivatives. The introduction of substituted amine side chain at quinolinium obviously increased the binding affinity of compounds to G-quadruplex DNA. It was also found that 1,3-disubstituted benzene derivatives and 1,4-disubstituted benzene derivatives had different effects on the conformation of G-quadruplex DNA by CD spectroscopy analysis. The differences for the interactions of these two classes of compounds with G-quadruplex were further studied and elaborated through molecular modeling experiments.