From solution phase to "on-column" chemistry: trichloroacetimidate-based glycosylation promoted by perchloric acid-silica

J Org Chem. 2005 Oct 28;70(22):9059-62. doi: 10.1021/jo051390g.

Abstract

[reaction: see text] Activation of ester-protected glycosyl trichloroacetimidate donors by perchloric acid immobilized on silica afforded 1,2-trans disaccharides in 60-90% yields. Applying this approach to one-pot sequential glycosylation resulted in efficient syntheses of the N-linked glycan trimannoside and Le(X) and Le(A) trisaccharides in very good yield (76%, 62%, and 59% yields, respectively). Solution phase reactions were also translated to a solid phase format; priming the top of a standard silica chromatography column with perchloric acid immobilized on silica facilitated "on-column" glycosylation with subsequent "in situ" purification of products. Coupling yields from this approach were comparable to those obtained from the corresponding solution-phase disaccharide couplings. A series of glycosylated amino acids were also synthesized in high yield with use of the on-column approach.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acetamides
  • Amino Acids / chemistry
  • Chloroacetates*
  • Glycosylation
  • Molecular Structure
  • Perchlorates / chemistry*
  • Silicon Dioxide / chemistry*
  • Sugar Alcohols / chemistry
  • Trichloroacetic Acid / chemistry

Substances

  • Acetamides
  • Amino Acids
  • Chloroacetates
  • Perchlorates
  • Sugar Alcohols
  • Trichloroacetic Acid
  • Silicon Dioxide
  • trichloroacetamide