Capsular polysaccharide of Streptococcus pneumoniae type 19F: synthesis of the repeating unit.
A new and more versatile synthesis of beta-D-ManpNAc-(1-->4)-alpha-D-Glcp-(1-->2)-alpha-L-Rhap, the trisaccharide repeating unit of the Streptococcus pneumoniae type 19F capsular polysaccharide, is described. The present approach allows a simple access to different fragments containing the trisaccharide and the conjugation of the product(s) to a protein through the selective manipulation of the anomeric position at the reducing end and of the HO-4 function at the nonreducing end. The synthetic scheme shows an efficient application of the sulfoxide method for the stereoselective and high yielding formation of the glycosidic linkages.
Bousquet
E
E
Istituto di Chimica Farmaceutica e Toss., Catania, Italy.
Khitri
M
M
Lay
L
L
Nicotra
F
F
Panza
L
L
Russo
G
G
D016667:Bacterial Capsules; D002240:Carbohydrate Sequence; D009682:Magnetic Resonance Spectroscopy; D008956:Models, Chemical; D008969:Molecular Sequence Data; D011135:Polysaccharides, Bacterial / Q000737:chemistry*; D013296:Streptococcus pneumoniae / Q000737:chemistry*
D011135:Polysaccharides, Bacterial; C116177:capsular polysaccharide 19F