A Guanosine-Based Self-Assembly as Enantioselective Catalyst Scaffold

A self-assembled G-quadruplex formed by guanosine and borate as chiral scaffold was used to catalyze the asymmetric Friedel-Crafts reaction in water. Catalysis, depends on self-assembly of guanosine and borate into a fibrillar structure in the presence of Cu2+ ion, can be modulated by assembly concentration, temperature and the amount of Cu2+ ion. Detailed spectral experiments proved that the guanosine-based assembly in solution were responsible for the enantioselective catalysis, rather than small-molecule species. Some of similar G-quartet assemblies were unable to promote the asymmetric reaction, implying the unique properties of the current system including excellent lifetime stability and supramolecular chiral structures. This work provided the first example of self-assembled G-quadruplex achieving enantioselective catalysis and some perspective to better understand the design of nucleoside-based self-assemblies for enantioselective reaction. In view of guanosine as building block, these findings may...