Signal transduction in oligoamide foldamers by selective non-covalent binding of chiral phosphates at a urea binding site

Abstract

Non-covalent interactions between a chiral phosphate anion and a urea binding site induce a conformational preference in an amide foldamer.

Internal acidity scale and reactivity evaluation of chiral phosphoric acids with different 3,3′-substituents in Brønsted acid catalysis

“…[47][48][49] Finally, there are various examples throughout organocatalysis, in which the substrate binding and activation via a hydrogen bonded species is proposed. [50][51][52][53][54] However, the central hydrogen-bonded species are oen in fast chemical exchange or have short lifetimes, therefore it is for most of the systems experimentally not possible to detect these hydrogen bonds.…”

Inducing a pH-dependent conformational response by competitive binding to Zn2+ of a series of chiral ligands of disparate basicity

“…Having demonstrated that pH-induced exchange of metalbound ligands could be used as a mechanism for the conformational communication of information, we next used it to induce a more extensive conformational change by relaying the induced conformation of the BQPA ligand into an induced screw-sense preference in a pendent foldamer. Complex Zn(8)•2ClO4 was synthesised (see the ESI), in which the achiral helical tetramer of the quaternary amino acid Aib 48 was ligated at its N-terminus to the Zn(1) binding site, and at its C terminus Please do not adjust margins Please do not adjust margins to a fifth (R)-Aib* residue that was enantioselectively labelled with 13 C in its pro-R enantiotopic methyl groups. 49 Peak separation in the 13 C-NMR spectrum allows such Aib* residues to act as reporters of local conformation, 50 thus indicating that pH has been translated into a conformational change and relayed to a remote site.…”

“…'Universal' indicators function through protonation of a series of indicators of increasing pKa, allowing the concentration of protons to be translated into a colorimetric output. 10 Artificial signalling systems have been designed with more biomimetic features such as spatial communication to remote sites, [11][12][13] agonist/antagonist functions, 14,15 and the ability to operate in the membrane phase. [16][17][18][19]…”

Synthesis and Dimerization Studies of a Lipophilic Photoresponsive Aryl‐Extended Tetraurea‐Calix[4]pyrrole

“…The development of supramolecular systems [1][2][3][4][5][6][7] able to switch between two or more different states by the effect of external stimuli is an attractive goal of supramolecular chemistry. [8][9][10] Stimuli-controllable multi-functional supramolecular systems emerge when each state features different properties and/or functions such as morphology,a ggregation, and molecular recognition. [11][12] To this end, light and heat are ideal external stimuli because they can produce the switching withouta ddition of external chemicals peciestot he systems.…”

“…The development of supramolecular systems able to switch between two or more different states by the effect of external stimuli is an attractive goal of supramolecular chemistry . Stimuli‐controllable multi‐functional supramolecular systems emerge when each state features different properties and/or functions such as morphology, aggregation, and molecular recognition .…”