beta(2,2)-Aminoxy acids: a new building block for turns and helices

J Am Chem Soc. 2002 Aug 28;124(34):9966-7. doi: 10.1021/ja026966n.

Abstract

The conformational properties of peptides 1-4 built from 3-aminoxy-2,2-dimethyl-propionic acid, a beta2,2-aminoxy acid, were investigated by NMR spectroscopy and X-ray crystallography. A novel beta N-O turn involving a nine-membered-ring intramolecular hydrogen bond between NHi+2 and COi was formed in diamides 1 and 2, which was further stabilized by another six-membered-ring intramolecular hydrogen bond between NHi+2 and NOi+1. Triamides 3 and 4 displayed a well-defined helical structure featuring two consecutive beta N-O turns. The X-ray structure of 4 revealed that the amide carbonyl group at position i+2 was twisted +65.9 degrees from that at i position, suggesting a novel 1.79 helix. Therefore, beta2,2-aminoxy acid can be used as a new building block for turns and helices.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amides / chemical synthesis
  • Amides / chemistry*
  • Models, Molecular
  • Nuclear Magnetic Resonance, Biomolecular
  • Peptides / chemical synthesis
  • Peptides / chemistry*
  • Propionates / chemistry*
  • Protein Structure, Secondary*

Substances

  • Amides
  • Peptides
  • Propionates