Synthesis and characterisation of helical beta-peptide architectures that contain (S)-beta3-HDOPA(Crown Ether) derivatives

Chemistry. 2008;14(10):3154-63. doi: 10.1002/chem.200701360.

Abstract

A new set of beta-amino acids that carry various crown ether receptors on their side chains of the general formula (S)-beta(3)-HDOPA(crown ether) (HDOPA: homo-3,4-dihydroxyphenylalanine; (crown ether): [15]crown-5 ([15-C-5]), [18]crown-6 ([18-C-6]), [21]crown-7 ([21-C-7]), 1,2-Benzo-[24]crown-8 ([Benzo-24-C-8]) and (R)-Binol-[20]crown-6 ([(R)-Binol-20-C-6])) was prepared. Peptides that are based on these new crowned beta-amino acids combined with (1S,2S)-ACHC (2-aminocyclohexanecarboxylic acid), which is known to be a potent 3(14)-helix inducer, to the hexamer level, with two crowned residues at the i and i+3 positions of the main-chain, were synthesized in solution by stepwise coupling using Boc-N(alpha)-protection (Boc: tert-butoxycarbonyl) and the EDC/HOAt C-activation method. Their conformational analysis was performed by using FTIR absorption, NMR and CD spectroscopy techniques. Our results are in full agreement with a 3(14)-helix conformation.

MeSH terms

  • Circular Dichroism / methods
  • Crown Ethers / chemistry*
  • Dihydroxyphenylalanine / chemistry*
  • Magnetic Resonance Spectroscopy / methods
  • Magnetic Resonance Spectroscopy / standards
  • Molecular Structure
  • Peptides / chemical synthesis*
  • Peptides / chemistry*
  • Protein Structure, Secondary
  • Reference Standards
  • Spectroscopy, Fourier Transform Infrared / methods
  • Stereoisomerism

Substances

  • Crown Ethers
  • Peptides
  • Dihydroxyphenylalanine