The present invention relates to diversely acetylated decasaccharides of formula (I) representative of two repeating units of Shigella flexneri serotype 2a O-antigen, conjugates and method of preparation thereof. These compounds exhibit antigenic properties and are particularly useful for the diagnosis of Shigella infection.
wherein R1 and R2 are as defined in claim 1.
Synthesis of an analog of a biosyntheticprecursor of lipid A containing four (S)-3-hydroxytetradecanoic acids was effected via an improved synthetic route to investigate the relationship between the bioactivity and the chirality of the 3-hydroxy fatty acid residues in lipid A. The S-analog inhibited endotoxin-induced interleukin-6 (IL-6) production from human peripheral whole blood cells more strongly