Skeletal rearrangement of seven-membered iminosugars: synthesis of (-)-adenophorine, (-)-1-epi-adenophorine and derivatives and evaluation as glycosidase inhibitors

Bioorg Med Chem. 2013 Aug 15;21(16):4803-12. doi: 10.1016/j.bmc.2013.03.035. Epub 2013 Apr 2.

Abstract

The mirror image of natural product (+)-adenophorine along with its 1-epi-, 1-homo-analogs and other derivatives have been synthesized and evaluated as glycosidase inhibitors. The synthetic strategy is based on the skeletal rearrangement of tetrahydroxylated C-alkyl azepanes obtained via a Staudinger/azaWittig/alkylation sequence starting from a sugar-derived azidolactol. Several organometallic species have been investigated for the alkylation step including organomagnesium, organolithium, organozinc, organoaluminum and organocerium reagents. While diallylzinc proved to be the most efficient to introduce an allyl substituent, disappointing results were obtained with the other organometallic species leading either to lower yields or no reaction. Enzymatic assays indicate that (-)-adenophorine is a moderate α-l-fucosidase inhibitor.

Keywords: Adenophorine; Azepane; Glycosidase inhibition; Iminosugar; Natural product.

MeSH terms

  • Alkylation
  • Animals
  • Aspergillus niger / enzymology
  • Aza Compounds / chemical synthesis*
  • Aza Compounds / chemistry
  • Aza Compounds / metabolism
  • Enzyme Inhibitors / chemical synthesis*
  • Enzyme Inhibitors / chemistry
  • Enzyme Inhibitors / metabolism
  • Glycoside Hydrolases / antagonists & inhibitors*
  • Glycoside Hydrolases / metabolism
  • Imino Sugars / chemical synthesis
  • Imino Sugars / chemistry*
  • Imino Sugars / metabolism
  • Oryza / enzymology
  • Protein Binding
  • Rats
  • Saccharomyces cerevisiae / enzymology
  • Stereoisomerism
  • alpha-L-Fucosidase / antagonists & inhibitors
  • alpha-L-Fucosidase / metabolism

Substances

  • Aza Compounds
  • Enzyme Inhibitors
  • Imino Sugars
  • adenophorine
  • Glycoside Hydrolases
  • alpha-L-Fucosidase