Article

Synthesis of beta-(1-->4)-oligo-D-mannuronic acid neoglycolipids.

Department of Chemistry, Lakehead University, 955 Oliver Road, Thunder Bay, Ontario, Canada P7B 5E1.
Carbohydrate Research (impact factor: 2.33). 01/2008; 343(1):7-17. DOI:10.1016/j.carres.2007.10.007 pp.7-17
Source: PubMed

ABSTRACT Mammalian Toll-like receptors (TLRs) play important roles in host immune defense. The activation of TLR and down-stream signaling pathways have great impact on human physiology. Chemically diverse microbial products as well as synthetic ligands serve as agonists for these receptors. Recently, synthetic TLR ligands are being exploited as useful therapeutic agents for a variety of diseases including infections, inflammatory diseases, and cancers. Alginate polymers and oligosaccharides are strong immune stimulants mediated by TLR2/4, but synthesis of alginate oligomers is rarely studied. Reported here are the design and chemical synthesis of two beta-(1-->4)-di- and beta-(1-->4)-tri-d-mannuronic acid neoglycolipids 1 and 2 as potential TLR ligands. By using 4,6-di-O-benzylidene-protected 1-thio mannoside 7 as a glycosyl donor, the diastereoselective beta-d-mannosylation protocol provides the beta-(1-->4)-d-mannobiose and beta-(1-->4)-d-mannotriose derivatives, which upon regioselective oxidation with TEMPO/BAIB oxidation system yield the corresponding beta-(1-->4)-d-mannuronic acid containing neoglycolipids 1 and 2.

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Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.

Keywords

4,6-di-O-benzylidene-protected 1-thio mannoside 7
 
Alginate polymers
 
chemical synthesis
 
Chemically diverse microbial products
 
diastereoselective beta-d-mannosylation protocol
 
down-stream signaling pathways
 
human physiology
 
Mammalian Toll-like receptors
 
neoglycolipids 1
 
potential TLR ligands
 
roles
 
synthetic TLR ligands
 
TEMPO/BAIB oxidation system yield
 
TLR
 
TLRs