Supramolecular assemblies involving salt bridges: DFT and X-ray evidence of bipolarity

Abstract

A series of pyridinium-carboxylate salts (1‒3) were designed, synthesized and structurally characterized to explore the importance of salt-bridge (SB) interactions in building self-assembled structures. We present a comprehensive analysis of...

Proton transfer mediated recognition of amines by ionizable macrocyclic receptors

“…As a consequence, receptor-assisted ionization may be used to provide additional stabilization to the host-guest complex by taking advantage of the electrostatic attraction of the ion pair. Ion pairing -triggered by proton transfer -as a design element in host-guest chemistry has seldom been used, 7 and this is surprising, given how heavily Nature relies on electrostatic interactions. For instance, ion pairing between the sidechain carboxylates of Asp or Glu and the nitrogen-containing basic moieties of Arg, Lys, or His is one of the type of bonds determining the tertiary structure of proteins.…”

“…Ion pairing – triggered by proton transfer – as a design element in host–guest chemistry has seldom been used, 7 and this is surprising, given how heavily Nature relies on electrostatic interactions. For instance, ion pairing between the side-chain carboxylates of Asp or Glu and the nitrogen-containing basic moieties of Arg, Lys, or His is one of the type of bonds determining the tertiary structure of proteins.…”

Supramolecular Self-Assembly Mediated by Multiple Hydrogen Bonds and the Importance of C–S···N Chalcogen Bonds in N′-(Adamantan-2-ylidene)hydrazide Derivatives

“… 37 Recently, authors have analyzed new types of supramolecular structures driven by salt bridge interactions and charge-assisted aromatic ring systems. 38 , 39 …”

“…In addition, the C–H···O interaction also participates in the stabilization of proteins and nucleic acids. − Crystallography and computational tools have been used to describe supramolecular assembly governed by charge-assisted hydrogen bonds in complexes of amino acid–carboxylic acid model systems . Recently, authors have analyzed new types of supramolecular structures driven by salt bridge interactions and charge-assisted aromatic ring systems. , …”

Replication of a synthetic oligomer using chameleon base-pairs

“…The amidine-benzoic acid interaction should be strong enough to ensure quantitative loading of monomers onto the template in non-polar solvents. [15][16][17][18][19][20][21][22][23] In the CuAAC ZIP step, intramolecular reactions on the template should be favoured relative to offtemplate intermolecular processes, leading to the salt bridge duplex. Hydrolysis of the ester linkers will cleave off the amidine recognition units, destroy the duplex, and release the original template along with the benzoic acid 3-mer copy.…”