Guanosine-Based Self-Assembly as an Enantioselective Catalyst Scaffold

Abstract

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

Impact of C-Terminal Chemistry on Self-Assembled Morphology of Guanosine Containing Nucleopeptides

“…The incorporation of G-quartet structures into supramolecular assemblies opens the possibility for nucleopeptides to be supramolecular catalysts. As other recent examples of guanine-based supramolecular structures have been shown to catalyze peroxidase reactions in the presence of hemin [35] and have provided a chiral scaffold for enantiomeric Freidel-Crafts alkylation [36], guanosine containing nucleopeptides should also be tested for emergent catalytic properties. Additionally, as the mutualism between nucleic acids and peptides in biological systems has positioned nucleopeptides [37] and co-assemblies of peptides and nucleic acids [38,39] as important systems in understanding chemical evolution, the self-assembled guanosine containing nucleopeptides reported in this study may inform future studies of dynamic chemical networks.…”

Competitive induction of circularly polarized luminescence of CdSe/ZnS quantum dots in a nucleotide–amino acid hydrogel

“…Hydrogels of Fmoc-Glu and dG/dA upon addition of K + ions It was known that guanosine based derivatives self-associated into G-quadruplexes ， which were composed with an arrangement of four guanine moieties connected together by eight hydrogenbonding interactions and stabilized by K + ions, and then the Gquartets stacked to form stable G-quadruplexes (G 4 ). 34,[44][45][46][47][48][49][50] However, it has been demonstrated that high-order aggregates for adenosine or deoxyadenosine upon addition of any alkali metal were unable to form. 49 Thus the K + ions were introduced into the system of Fmoc-Glu/dG and Fmoc-Glu/dA co-gels.…”

Recent Advances in Selected Asymmetric Reactions Promoted by Chiral Catalysts: Cyclopropanations, Friedel–Crafts, Mannich, Michael and Other Zinc-Mediated Processes—An Update

“…At the end of this chapter, it is worth mentioning a few more non-obvious approaches to the asymmetric Friedel-Crafts reaction. They are for sure the use of N-heterocyclic carbenes as catalysts in the synthesis of indole-fused polycyclic alcohols [56], guanosinebased self-assembly as catalytic system [57], and various DNA-employing catalytic systems [58][59][60].…”