AAAA–DDDD Quadruple H-Bond-Assisted Ionic Interactions: Robust Bis(guanidinium)/Dicarboxylate Heteroduplexes in Water

Abstract

The use of geminal di(guanidinium) and acridin-9(10H)-one-derived di(carboxylate) derivatives (1a− c and 2a−e, respectively) allows stabilization of heterodimers characterized by high binding affinities in water (maximum ΔG < −7 kcal mol −1 , K a > 10 5 M −1 ) as inferred from UV−vis spectroscopic titrations and ITC measurements, therefore rivaling or surpassing the interaction energy between the strongest DNA or RNA triplet pairs. These duplexes are readily accessible and are structurally modifiable, rendering them attractive as building blocks for creating heteroduplex constructs. Incorporating poly(ethylene glycol)-decorated benzyl groups into the dicarboxylate, allows formation of hydrogels in the case of 1b−2c.

Autocatalytic and oscillatory reaction networks that form guanidines and products of their cyclization

“…Herein we link the chemistry of thiol to reactions that form guanidines and the products of their follow-up transformations. These compounds form strong hydrogen bonds, interact with polyanions 46 , and are commonly involved in selective molecular recognition and self-assembly 64 – 66 . In this work, we have already shown how by incorporating a cascade cyclization into an oscillatory network the oscillations of a dihydropyrimidine-based heterocycle can be created.…”

Controlling Keto–Enol Tautomerism of Ureidopyrimidinone to Generate a Single-Quadruple AADD-DDAA Dimeric Array

“…Structure control of intramolecular proton tautomerism is the basis for the functionality of biomacromolecules such as DNA and proteins and has inspired a fruitful research area of supramolecular chemistry. − Meijer and co-workers studied in detail the effect of substituents on the equilibrium of tautomers . The change of the electronic properties of substituents on the monomers can significantly influence the stability of complex.…”

Photo‐Controlled Macroscopic Self‐Assembly Based on Photo‐Switchable Hetero‐Complementary Quadruple Hydrogen Bonds

“…This might be attributed to that it is challengeable to sufficiently photo‐regulate the binding affinity of H‐bonding interactions between the macroscopic interfaces. Among the multiple H‐bonding arrays, the hetero‐complementary multiple H‐bonding motifs are distinguished by the unique ability of associating two different partners with high fidelity and tunable affinity, [60–63] which is highly expectable to achieve H‐bonded MSA processes [64–67] . Therefore, developing hetero‐complementary multiple H‐bonding motifs with distinctly photo‐switchable binding behavior, is of great advantageous for the construction of intelligent photo‐responsive H‐bonded MSA materials with more innovative and practical applications.…”