A Convergent Route to Enantiomers of the Bicyclic Monosaccharide Bradyrhizose Leads to Insight into the Bioactivity of an Immunologically Silent Lipopolysaccharide

• Author(s) / Creator(s)

  • Claude Larrivée Aboussafy
  • Lotte Bettina Anderson Gersby
  • Antonio Molinaro
  • Mari-Anne Newman
  • Todd L. Lowary

• The synthesis of bradyrhizose, the monosaccharide component of the lipopolysaccharide O-antigen of the nitrogen-fixing bacteria Bradyrhizobium sp. BTAi1 and sp. ORS278, has been achieved in 25 steps in an overall yield of 6% using myo-inositol and ethyl propiolate as the starting materials. The route involved the late state resolution of a racemic intermediate to provide both enantiomers of this unusual bicyclic monosaccharide. Both the natural D-enantiomer, and the unnatural and heretofore unknown L-enantiomer, were converted to disaccharide derivatives containing different forms of the monosaccharide (D,D; L,L; D,L; L,D). Evaluation of the synthetic compounds for their ability to act as microbe-associated molecular patterns in plants, through induction of reactive oxygen species, was investigated. These experiments suggest that the immunologically-silent nature of the natural glycans is due to specific structural features.

• Date created

  2019-01-27

• Subjects / Keywords

  • Immunomodulator
  • Synthesis
  • Monosaccharide
  • Bicyclic

• Type of Item

  Article (Published)

• DOI

  https://doi.org/10.7939/R3DN40C2J

• License

  Attribution-NonCommercial-NoDerivatives 4.0 International