Taxonomic group: bacteria / Proteobacteria
(Phylum: Proteobacteria)
Host organism: Homo sapiens
Associated disease: diarrhea [ICD11:
ME05.1 
, ICD11:
SA55 
];
hemolytic-uremic syndrome (HUS) [ICD11:
3A21.2 
];
infection due to Escherichia coli [ICD11:
XN6P4 
]
Publication DOI: 10.1055/s-0035-1562606Journal NLM ID: 9203577Publisher: Stuttgart; New York: Thieme Medical Publishers, Inc., Georg Thieme Verlag
Correspondence: pintuchem06

gmail.com
Institutions: Medicinal and Process Chemistry Division, CSIR-Central Drug Research Institute, BS-10/1, Sector 10, Jankipuram extension, Sitapur Road, Lucknow, 226 031, India, Academy of Scientific and Innovative Research, New Delhi, India
The synthesis of the tetrasaccharide repeating unit of the O-antigen of Escherichia coli O163 as its p-methoxyphenyl (PMP) glycoside was achieved followed by sequential glycosylation strategy through thioglycoside activation using sulfuric acid immobilized on silica (H2SO4-silica) in conjunction with N-iodosuccinimide as a Bronsted acid catalyst. The application of one-pot reaction conditions for two glycosylations and in situ PMB-group removal reduced the number of reaction steps significantly. The l-QuipNAc building block was obtained from known carbohydrate l-rhamnose precursors. The stereoselective outcomes of all glycosylation reactions were found to be very good. A late-stage TEMPO-mediated oxidation was performed for the formation of required uronic acid moiety. An analogue of the target tetrasaccharide was also prepared by using one-pot glycosylation approach. Such synthetic oligosaccharides could later be effectively conjugated with an appropriate protein to furnish glycoconjugate derivatives for their use in immunochemical studies.
antigen, polysaccharide, O-antigen, Escherichia coli, glycosylation, glycoconjugate, stereoselectivity
Structure type: suggested polymer biological repeating unit
Location inside paper: p.2582, fig.1
Compound class: O-polysaccharide, O-antigen
Contained glycoepitopes: IEDB_115136,IEDB_137485,IEDB_140630,IEDB_141807,IEDB_144983,IEDB_151531,IEDB_152206,IEDB_423153,IEDB_983930,SB_44,SB_72
Methods: 13C NMR, 1H NMR, NMR-2D, TLC, ESI-MS, chemical synthesis, chemical methods, NMR-1D, glycosylation
Comments, role: chemical repeat frame is different in the paper
Related record ID(s): 11509, 30649
NCBI Taxonomy refs (TaxIDs): 2100520Reference(s) to other database(s): GTC:G12313TT
Show glycosyltransferases
There is only one chemically distinct structure: