Taxonomic group: bacteria / Proteobacteria
(Phylum: Proteobacteria)
Host organism: Homo sapiens
Associated disease: diarrhea [ICD11:
ME05.1 
, ICD11:
SA55 
];
hypotension [ICD11:
BA2Y 
, ICD11:
BA2Z 
]
Publication DOI: 10.1002/ejoc.200700322Journal NLM ID: 9805750Publisher: Wiley-VCH
Correspondence: kpn

helix.nih.gov
Institutions: NIDDK, LBC, Section on Carbohydrates, National Institutes of Health, Bethesda, MD 20892-0815, USA
The fragments described contain a galactose residue with cyclic 4,6-phosphate and are equipped with an amino-functionalized spacer, allowing further derivatization or direct conjugation to suitable carriers. The core Gal-(1-3)-GlcNAc disaccharide was obtained by condensation of 8-azido-3,6-dioxaoctyl 2-acetamido-4,6-O-benzylidene-2-deoxy-b-D-glucopyranoside with 2,3,4,6-tetra-O-acetyl-a-D-galactopyranosyl bromide under Helferich conditions. Reductive opening of the benzylidene acetal, followed by deacetylation and selective benzylation gave 8-azido-3,6-dioxaoctyl 2-acetamido-6-O-benzyl-3-O-(3-O-benzyl-b-D-galactopyranosyl)-2-deoxy-b-D-glucopyranoside, which was regioselectively phosphorylated to give two isomeric 4,6-cyclic 2,2,2-trichloroethyl phosphates. The (R) phosphate was subjected to catalytic hydrogenation/hydrogenolysis to give the fully deprotected title disaccharide fragment. Glycosylation of the (S)-phosphate diol with 2,4-di-O-benzyl-3,6-dideoxy-a-L-xylo-hexopyranosyl bromide under halide-asisted conditions yielded a mixture of the tetrasaccharide and a trisaccharide, which were readily separable by chromatography. Their hydrogenation/hydrogenolysis effected global deprotection as well as reduction of the azide, to furnish the deprotected.
carbohydrates, Oligosaccharides, glycosylation, conjugate vaccine, regioselective phosphorylation
Structure type: oligomer
Location inside paper: p.4367, fig.1,2
Aglycon: spacer-squaric acid
Trivial name: fragment of hexasaccharide repeating unit of O-antigen
Contained glycoepitopes: IEDB_136044,IEDB_137472,IEDB_141794,IEDB_190606,SB_165,SB_166,SB_187,SB_195,SB_7,SB_88
Methods: 13C NMR, 1H NMR, 31P NMR, chemical synthesis
Synthetic data: chemical
Related record ID(s): 23631, 23941, 23942
NCBI Taxonomy refs (TaxIDs): 45888Reference(s) to other database(s): GTC:G79390FX, GlycomeDB:
37327
Show glycosyltransferases
There is only one chemically distinct structure: