Peptide-catalyzed conversion of racemic oxazol-5(4H)-ones into enantiomerically enriched α-amino acid derivatives

J Org Chem. 2014 Feb 21;79(4):1542-54. doi: 10.1021/jo402828f. Epub 2014 Feb 12.

Abstract

We report the development and optimization of a tetrapeptide that catalyzes the methanolytic dynamic kinetic resolution of oxazol-5(4H)-ones (azlactones) with high levels of enantioinduction. Oxazolones possessing benzylic-type substituents were found to perform better than others, providing methyl ester products in 88:12 to 98:2 er. The mechanism of this peptide-catalyzed process was investigated through truncation studies and competition experiments. High-field NOESY analysis was performed to elucidate the solution-phase structure of the peptide, and we present a plausible model for catalysis.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Amino Acids / chemical synthesis*
  • Amino Acids / chemistry*
  • Catalysis
  • Magnetic Resonance Spectroscopy
  • Molecular Structure
  • Oxazoles / chemistry*
  • Oxazolone / chemistry*
  • Peptides / chemistry*
  • Stereoisomerism

Substances

  • Amino Acids
  • Oxazoles
  • Peptides
  • Oxazolone