138906-41-9Relevant articles and documents
Zwitterionic Polysaccharides of Shigella sonnei: Synthetic Study toward a Ready-for-Oligomerization Building Block Made of Two Rare Amino Sugars
Pfister, Hélène B.,Paoletti, Julie,Poveda, Ana,Jimenez-Barbero, Jesus,Mulard, Laurence A.
, p. 4270 - 4282 (2018)
Shigellosis is an endemic diarrheal disease caused by Gram negative bacteria named Shigella. The most exposed polysaccharides of Shigella sonnei display a zwitterionic disaccharide repeating unit (AB) made of two rare amino sugars: [4)-α- l -Alt p NAcA-(1→3)-β- d -Fuc p NAc4N-(1→]. An original synthesis of a ready-for-oligomerization AB disaccharide is reported. The targeted orthogonally protected disaccharide was synthesized from l -glucose and tetra- O -acetyl-β- d -glucosamine. The challenging introduction of the 4 B -azido group masking the amino moiety of the AAT residue was performed at the disaccharide stage by a two-step procedure (triflation followed by nucleoaphilic displacement with NaN 3). A post-glycosylation oxidation strategy was employed to access the altruronate moiety.
NOVEL INTERMEDIATES FOR THE PREPARATION OF GBS POLYSACCHARIDE ANTIGENS
-
Paragraph 0066-0068, (2019/01/30)
The present invention generally refers to novel intermediate polysaccharide units, useful for the preparation of polysaccharide antigen of GBS Ia, Ib and III; the invention also refers to a process for their preparation and their use as intermediate for t
Synthesis and immunological characterization of modified hyaluronic acid hexasaccharide conjugates
Gu, Guofeng,Adabala, Pal John Pal,Szczepina, Monica G.,Borrelli, Silvia,Pinto, B. Mario
, p. 8004 - 8019 (2013/09/12)
The synthesis of a tetanus toxoid (TT)-conjugate of a hyaluronic acid (HA) hexasaccharide is described. The compound was intended for use in monitoring HA levels as a disease marker and as a potential vaccine against Group A Streptococcus (GAS) infections. We also report the synthesis of a chemically modified HA-hexasaccharide-TT conjugate in which the N-acetyl moiety of the N-acetyl-d-glucosamine residue is replaced with an N-propionyl unit in order to enhance immunogenicity. The oligosaccharides are synthesized in a convergent manner. The TT-conjugate syntheses rely on the reaction of the amines on the 6-aminohexyl aglycon of the hexasaccharides with diethyl squarate to give the monoethyl squarate adducts. Subsequent reactions with lysine ε-amino groups on TT then give the glycoconjugates containing an average of 8 hexasaccharide haptens per TT molecule. Immunological studies in mice show very similar antibody responses with both conjugates, suggesting that the N-acetyl groups of the glucosaminyl residues of the HA-hexasaccharide are not a critical part of the epitope recognized by the anti-HA polyclonal immune response. Furthermore, it would appear that the N-acyl moieties are not in close contact with the amino acid residues of the antibody combining sites.
