Controlling molecularity and stability of hydrogen bonded G-quadruplexes by modulating the structure's periphery.

We report on self-assembly of guanosines with aromatic esters at their 5'-position. Depending on the basicity of the 5'-ester either discrete octamers G8·K(+)I(-) or hexadecamers G16·3K(+)3I(-) are formed. The thermodynamic and kinetic stabilities of the G-quadruplex can be controlled by interlayer hydrogen-bonding and by dispersion interactions on the assembly's periphery.