New sugars from antigenic lipopolysaccharides of bacteria: identification and synthesis of 3-O-[(R)-1-carboxyethyl]-L-rhamnose, an acidic component of Shigella dysenteriae type 5 lipopolysaccharide.
A new acidic sugar, 3-O-[(R)-1-carboxyethyl]-L-rhamnose (1), has been identified as a constituent of the O-antigenic lipopolysaccharide of Sh. dysenteriae type 5. The structure of 1 has been established by physico-chemical methods and by synthesis. Alkylation of methyl 2,5-di-O-benzyl-alpha-L-rhamnofuranoside (6) with (S)- or (R)-2-chloropropionic acids, followed by removal of the protecting groups, afforded 3-O-[(R)-1-carboxyethyl]-L-rhamnose (9) and 3-O-[(S)-1-carboxyethyl]-L-rhamnose (10), respectively. The properties of 1 coincide with those of 9.
D000942:Antigens, Bacterial; D006863:Hydrogen-Ion Concentration; D008070:Lipopolysaccharides / Q000032:analysis* / Q000276:immunology; D012210:Rhamnose / Q000031:analogs & derivatives* / Q000032:analysis; D012762:Shigella dysenteriae / Q000032:analysis* / Q000276:immunology
D000942:Antigens, Bacterial; D008070:Lipopolysaccharides; D012210:Rhamnose