Guanine-Based G-Quadruplexes Templated by Various Cations toward Potential Use as Single-Ion Conductors

Inspired by the atomic-sized, shape-regulated features of G-quadruplexes comprising guanine motifs with a monovalent metal cation, the G-quadruplex-forming ability, and properties of a guanine-based pi-conjugated Y2 molecule containing bithiophene and peripheral dodecyl chain units in the presence of various cation salts (Li+, Na+, K+, and Mg2+) were exploited. A series of structural characterization revealed that Y2 yielded desirable G-quadruplexes with all the tested cations as a consequence of the combination of a hydrogen-bonded cyclic G-quartet, pi-stacking, and cation-dipole interactions. The radius and nature of the coordinating cations crucially affected the structural characteristics of G-quadruplexes, leading to variations in the ion migration ability inside the cavity of the G-quadruplex (Li+>Na+>K+>Mg2+), as characterized through theoretical and experimental investigations. These results not only improve the understanding of G-quadruplex self-assemblies based on guanine but also provide an impetus for their diverse potential applications, especially in the field of Li batteries.

Automated summary

Inspired by guanine motifs, the G-quadruplex-forming ability of a guanine-based Y2 molecule containing bithiophene and peripheral dodecyl chain units in the presence of different cation salts was investigated. The structural characterization revealed that the radius and nature of the coordinating cations crucially affected the structural characteristics and ion migration ability of G-quadruplexes.