Synthesis of the globotetraose tetrasaccharide and terminal tri- and di-saccharide fragments

Carbohydr Res. 1994 Jan 15:252:117-36. doi: 10.1016/0008-6215(94)90010-8.

Abstract

The 2-(trimethylsilyl)ethyl (TMSEt) beta-glycosides of globotetraose [beta-D-GalNAc-(1-->3)-alpha-D-Gal-(1-->4)-beta-D-Gal-(1-->4)-D-Glc] and the terminal trisaccharide, as well as the methyl alpha-glycoside 1 of the terminal disaccharide, were synthesised by silver trifluoromethanesulfonate-promoted beta-glycosylation of suitably protected galactoside, galabioside, and globotrioside alcohols with 3,4,6-tri-O-acetyl-2-deoxy-2-phthalimido-beta-D-galactopyranosyl chloride, followed by removal of protecting groups. Removal of the anomeric TMSEt group of the globotetraoside and of the terminal trisaccharide, using trifluoroacetic acid-dichloromethane, gave the corresponding hemiacetal sugars 8 and 3. The TMSEt glycoside of the terminal trisaccharide was converted, via the 1-acetate, into the corresponding isobutyl (4) and 3-butylsulfonyl-2-[(butylsulfonyl)methyl]propyl (5) glycosides and into the TMSEt thioglycoside 6 via the glycosyl bromide.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antigens / chemistry
  • Carbohydrate Sequence
  • Disaccharides / chemical synthesis*
  • Globosides / chemistry*
  • Molecular Sequence Data
  • Oligosaccharides / chemical synthesis*
  • Trisaccharides / chemical synthesis*

Substances

  • Antigens
  • Disaccharides
  • Globosides
  • Oligosaccharides
  • Trisaccharides
  • globotetraose