N-Aminoazetidinecarboxylic Acid: Direct Access to a Small-Ring Hydrazino Acid
摘要:
A short and efficient synthesis of the previously unknown N-aminoazetidinecarboxylic acid has been established using a photochemical [2 + 2] cycloaddition strategy starting from 6-azauracil. Chiral derivatization with a nonracemic oxazolidinone provided access to both en-antiomers of the title product.
Reactivity of 1-aminoazetidine-2-carboxylic acid during peptide forming procedures: observation of an unusual variant of the hydrazino turn
作者:Amandine Altmayer-Henzien、Valérie Declerck、Régis Guillot、David J. Aitken
DOI:10.1016/j.tetlet.2012.11.112
日期:2013.2
Peptide formation on the N-terminal of 1-aminoazetidine-2-carboxylic acid is rendered problematic due to a ring opening reaction. However C-terminal development is possible and two diastereomeric mixed hydrazino dipeptides were prepared. Solution-state studies of these compounds suggest the presence of intramolecular hydrogen bonding, consistent with a hydrazino turn, and the crystal structure of one
Fine Tuning of β-Peptide Foldamers: a Single Atom Replacement Holds Back the Switch from an 8-Helix to a 12-Helix
作者:Amandine Altmayer-Henzien、Valérie Declerck、Jonathan Farjon、Denis Merlet、Régis Guillot、David J. Aitken
DOI:10.1002/anie.201504126
日期:2015.9.7
length. While tACBC homooligomers assume a dominant 12‐helix conformation, the aza‐primed oligomers preferentially adopt a stabilized 8‐helix conformation for an oligomer length up to 6 residues. The (formal) single‐atom exchange at the N terminus of a tACBC oligomer thus contributes to the sustainability of the 8‐helix, which resists the switch to a 12‐helix. This effect illustrates atomic‐level programmable
Strategic C to N Replacement in β-Peptides: Atomic Level Control of Helical Folding
作者:Valérie Declerck、David J. Aitken
DOI:10.1021/acs.joc.8b01096
日期:2018.8.3
Single residue control of the helical topology of beta-peptides is a contemporary challenge in foldamer science. We present the conformational preferences of oligomers of trans-2-aminocyclobutanecarboxylic acid (tACBC), in which a central residue has been replaced by a single N-aminoazetidine-2-carboxylic acid (AAzC) moiety. The latter has such a strong demand for local 8-helical conformers that the usual 12-helix secondary structure of a tACBC octamer is switched to a fully 8-helical conformation as a result of the single residue substitution.