AI Article Synopsis
- The study presents an effective method for the asymmetric synthesis of β(2)-aminoxy acids and explores their peptide conformations through both experimental and theoretical approaches.
- It reveals that intramolecular hydrogen bonding, specifically β N-O turns, occurs between adjacent amino acid residues, leading to the formation of helical structures in solution.
- Although helical and reverse-turn structures are nearly equally stable, variations in conformations of β(2)-aminoxy monomers are noted in both solid and solution states based on X-ray and 2D NOESY analyses.
Article Abstract
Herein, we report an efficient route for the asymmetric synthesis of β(2)-aminoxy acids as well as experimental and theoretical studies of conformations of peptides composed of β(2)-aminoxy acids. The nine-membered-ring intramolecular hydrogen bonds, namely, β N-O turns, are generated between adjacent residues in those peptides, in accordance with our computational results. The presence of two consecutive homochiral β N-O turns leads to the formation of β N-O helical structures in solution, although both helical (composed of two β N-O turns of the same handedness) and reverse-turn (composed of two β N-O turns with opposite handedness) structures are of similar stability, as suggested by theoretical studies. Nevertheless, two slightly different conformations, with the same handedness, of β(2)-aminoxy monomers have been observed in the solid state and in solution according to our X-ray and 2D NOESY studies.
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| http://dx.doi.org/10.1002/asia.201000933 | DOI Listing |
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