Biomaterial Database

Di- and tri-saccharide glycosyl donors for the synthesis of fragments of the O-specific antigen of Shigella dysenteriae type 1. 1993

P Kovác

NIDDK, National Institutes of Health, Bethesda, Maryland 20892.

Methyl O-(2,4-di-O-benzoyl-3-O-bromoacetyl-alpha-L-rhamnopyranosyl)-(1-->3)- 2,4-di-O-benzoyl-alpha-L-rhamnopyranoside was treated with dichloromethyl methyl ether and ZnCl2 to give O-(2,4-di-O-benzoyl-3-O-bromoacetyl-alpha-L-rhamnopyranosyl)-(1-->3)2,4- di-O- benzoyl-alpha-L-rhamnopyranosyl chloride. Similar treatment of methyl O-(3,4,6-tri-O-acetyl-2-azido-2-deoxy-alpha-D- glucopyranosyl)-(1-->3)-2,4-di-O-benzoyl-alpha-L-rhamnopyranoside (13) gave crystalline O-(3,4,6-tir-O-acetyl-2-azido-2-deoxy-alpha-D-glucopyranosyl)-(1-- >3)-2,4-di-O- benzoyl-alpha-L-rhamnopyranosyl chloride (14), which was also obtained by treatment of methyl O-(3,4,6-tri-O-acetyl-2-azido-2-deoxo-alpha-D- glucopyranosyl)-(1-->3)-2,4-di-O-benzoyl-1-thio-alpha-L-rhamnopyranoside (12) with chlorine. In contrast to the conversion 12-->14, which was stereospecific, the reaction of methyl O-(3,4,6-tri-O-acetyl-2-azido-2- deoxy-alpha-D-glucopyranosyl)-(1-->3)-(O-2,4-di-O-benzoyl-alpha-L- rhamnopyranosyl)-(1-->3)-2,4-di-O-benzoyl-1-thio-alpha-L-rhamnopyrano sid e with chlorine gave a mixture of the corresponding alpha- (16) and beta- (17) glycosyl chlorides. Condensation of the mixed chlorides 16 and 17 with 1,3,4,6-tetra-O-acetyl-alpha-D-galactopyranose, followed by reduction-acetylation of the product, gave a fully protected derivative of the tetrasaccharide alpha-D-Glc pNAc-(1-->3)-alpha-L-Rhap-(1-->3)-alpha-L-Rhap-(1-->2) -alpha-D-Galp.

UI	MeSH Term	Description	Entries
D007202	Indicators and Reagents	Substances used for the detection, identification, analysis, etc. of chemical, biological, or pathologic processes or conditions. Indicators are substances that change in physical appearance, e.g., color, at or approaching the endpoint of a chemical titration, e.g., on the passage between acidity and alkalinity. Reagents are substances used for the detection or determination of another substance by chemical or microscopical means, especially analysis. Types of reagents are precipitants, solvents, oxidizers, reducers, fluxes, and colorimetric reagents. (From Grant & Hackh's Chemical Dictionary, 5th ed, p301, p499)	Indicator,Reagent,Reagents,Indicators,Reagents and Indicators
D008969	Molecular Sequence Data	Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.	Sequence Data, Molecular,Molecular Sequencing Data,Data, Molecular Sequence,Data, Molecular Sequencing,Sequencing Data, Molecular
D011135	Polysaccharides, Bacterial	Polysaccharides found in bacteria and in capsules thereof.	Bacterial Polysaccharides
D002236	Carbohydrate Conformation	The characteristic 3-dimensional shape of a carbohydrate.	Carbohydrate Linkage,Carbohydrate Conformations,Carbohydrate Linkages,Conformation, Carbohydrate,Conformations, Carbohydrate,Linkage, Carbohydrate,Linkages, Carbohydrate
D002240	Carbohydrate Sequence	The sequence of carbohydrates within POLYSACCHARIDES; GLYCOPROTEINS; and GLYCOLIPIDS.	Carbohydrate Sequences,Sequence, Carbohydrate,Sequences, Carbohydrate
D004187	Disaccharides	Oligosaccharides containing two monosaccharide units linked by a glycosidic bond.	Disaccharide
D012762	Shigella dysenteriae	A species of gram-negative, facultatively anaerobic, rod-shaped bacteria that is extremely pathogenic and causes severe dysentery. Infection with this organism often leads to ulceration of the intestinal epithelium.	Bacillus dysenteriae,Bacillus dysentericus,Bacillus shigae,Eberthella dysenteriae,Shigella shigae
D013329	Structure-Activity Relationship	The relationship between the chemical structure of a compound and its biological or pharmacological activity. Compounds are often classed together because they have structural characteristics in common including shape, size, stereochemical arrangement, and distribution of functional groups.	Relationship, Structure-Activity,Relationships, Structure-Activity,Structure Activity Relationship,Structure-Activity Relationships
D014312	Trisaccharides	Oligosaccharides containing three monosaccharide units linked by glycosidic bonds.	Trisaccharide
D019081	O Antigens	The lipopolysaccharide-protein somatic antigens, usually from gram-negative bacteria, important in the serological classification of enteric bacilli. The O-specific chains determine the specificity of the O antigens of a given serotype. O antigens are the immunodominant part of the lipopolysaccharide molecule in the intact bacterial cell. (From Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)	O-Antigen,O-Specific Polysaccharides,O Antigen,O Antigen, Bacterial,O-Antigens,O-Specific Polysaccharide,Antigen, Bacterial O,Antigen, O,Antigens, O,Bacterial O Antigen,O Specific Polysaccharide,O Specific Polysaccharides,Polysaccharide, O-Specific,Polysaccharides, O-Specific