Efficient blockwise synthesis of pyruvated di- and trisaccharide fragments related to Klebsiella K26 capsular polysaccharides

Article abstract of DOI:10.1002/prac.19963380148

Pyruvated di- and trisaccharide fragments representing the immunodominant side chains of Klebsiella K26 capsular polysaccharides are prepared. Phenyl 4′,6′-O-benzylidene-1-thio-β-D-lactoside (1) is converted in 4 steps into the corresponding pyruvated 1-thio-lactoside (2) and transformed into the imidate (4). Coupling of the latter with Z-protected 5-aminopentanol gives the pyruvated disaccharide fragment (6) upon deblocking. Similarly, imidate (4) is coupled to allyl 2,3-di-O-benzoyl-3-O-(1-fluoro-1,1,3,3-tetraisopropyl-1,3-disiloxane-3-yl)- α-D-glucopyranoside (8) to give the corresponding trisaccharide fragment upon deblocking. Johann Ambrosius Barth 1996.