Synthesis of a library of allyl α-l-arabinofuranosyl-α- or β-d-xylopyranosides; route to higher oligomers
摘要:
Six isomeric disaccharides allyl 2,3,5-tri-O-benzoyl-alpha-L-arabinofuranosyl-alpha-D-xylopyranosides and beta-D-xylopyranosides were synthetized by the stereoselective glycosylation of pure allyl alpha- or beta-D-xylopyranosides with 1-O-acetyl-2,3,5-tri-O-benzoyl-L-arabinofuranose as donor, catalyzed with BF3.Et2O in DCM. Regio- and stereoselective glycosylation with excess of donor furnished almost exclusively the trisaccharides allyl 2,3-di-O-(2,3,5-tri-O-benzoyl-alpha-L-arabinofuranosyl)-alpha- or beta-D-xylopyranosides. Extension of the reaction to the triol beta-D-xylopyranosyl-(1 -> 4)-1,2,3-tri-O-acetyl-alpha-D-xylopyranose, obtained from the 4-hydroxyl penta-O-acetyl-alpha-xylobiose, gave in the same manner the tetrasaccharide [2,3-di-O-(2,3,5-tri-O-benzoyl-alpha-L-arabinofuranosyl)-beta-D-xylopyranosyl]-(1 -> 4 )-1,2,3-tri-O-acetyl-alpha-D-xylopyranose. The protocol described herein should offer the possibility to produce branched oligosaccharides with a 2,3-di-O-(alpha-L-Ara(f))-beta-D-Xyl(p) block unit at the terminal non-reducing end. (c) 2007 Elsevier Ltd. All rights reserved.
Synthesis of a library of allyl α-l-arabinofuranosyl-α- or β-d-xylopyranosides; route to higher oligomers
摘要:
Six isomeric disaccharides allyl 2,3,5-tri-O-benzoyl-alpha-L-arabinofuranosyl-alpha-D-xylopyranosides and beta-D-xylopyranosides were synthetized by the stereoselective glycosylation of pure allyl alpha- or beta-D-xylopyranosides with 1-O-acetyl-2,3,5-tri-O-benzoyl-L-arabinofuranose as donor, catalyzed with BF3.Et2O in DCM. Regio- and stereoselective glycosylation with excess of donor furnished almost exclusively the trisaccharides allyl 2,3-di-O-(2,3,5-tri-O-benzoyl-alpha-L-arabinofuranosyl)-alpha- or beta-D-xylopyranosides. Extension of the reaction to the triol beta-D-xylopyranosyl-(1 -> 4)-1,2,3-tri-O-acetyl-alpha-D-xylopyranose, obtained from the 4-hydroxyl penta-O-acetyl-alpha-xylobiose, gave in the same manner the tetrasaccharide [2,3-di-O-(2,3,5-tri-O-benzoyl-alpha-L-arabinofuranosyl)-beta-D-xylopyranosyl]-(1 -> 4 )-1,2,3-tri-O-acetyl-alpha-D-xylopyranose. The protocol described herein should offer the possibility to produce branched oligosaccharides with a 2,3-di-O-(alpha-L-Ara(f))-beta-D-Xyl(p) block unit at the terminal non-reducing end. (c) 2007 Elsevier Ltd. All rights reserved.
Synthesis of a library of allyl α-l-arabinofuranosyl-α- or β-d-xylopyranosides; route to higher oligomers
作者:Jean-Pierre Utille、Isabelle Jeacomine
DOI:10.1016/j.carres.2007.08.007
日期:2007.12
Six isomeric disaccharides allyl 2,3,5-tri-O-benzoyl-alpha-L-arabinofuranosyl-alpha-D-xylopyranosides and beta-D-xylopyranosides were synthetized by the stereoselective glycosylation of pure allyl alpha- or beta-D-xylopyranosides with 1-O-acetyl-2,3,5-tri-O-benzoyl-L-arabinofuranose as donor, catalyzed with BF3.Et2O in DCM. Regio- and stereoselective glycosylation with excess of donor furnished almost exclusively the trisaccharides allyl 2,3-di-O-(2,3,5-tri-O-benzoyl-alpha-L-arabinofuranosyl)-alpha- or beta-D-xylopyranosides. Extension of the reaction to the triol beta-D-xylopyranosyl-(1 -> 4)-1,2,3-tri-O-acetyl-alpha-D-xylopyranose, obtained from the 4-hydroxyl penta-O-acetyl-alpha-xylobiose, gave in the same manner the tetrasaccharide [2,3-di-O-(2,3,5-tri-O-benzoyl-alpha-L-arabinofuranosyl)-beta-D-xylopyranosyl]-(1 -> 4 )-1,2,3-tri-O-acetyl-alpha-D-xylopyranose. The protocol described herein should offer the possibility to produce branched oligosaccharides with a 2,3-di-O-(alpha-L-Ara(f))-beta-D-Xyl(p) block unit at the terminal non-reducing end. (c) 2007 Elsevier Ltd. All rights reserved.