부산대학교 도서관

G-quadruplex (G4) is the most well-known noncanonical conformation of DNA involved in diverse pharmacological and biological contexts. G4 ligands have been extensively developed as molecular probes and tumor therapeutic reagent candidates. Currently used ligands are commonly aromatic, planar, and electron deficient for effective interaction with quadruplex-stranded DNAs. We recognized that tropylium cations possess the aforementioned features of effective quadruplex ligands. In this study, we prepared tropylium derivatives to validate their binding affinity with G4 and i-motif. Titration experiments revealed interaction between quadruplex structures and tropylium derivatives. We propose tropylium derivatives as new structural motifs indicating quadruplex-specific binding abilities. Our ligands possess the following advantages: small size, facile synthesis, and high solubility in aqueous conditions.