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Efficient Synthesis of the Lewis A Tandem Repeat. | LitMetric

Efficient Synthesis of the Lewis A Tandem Repeat.

Molecules

Department of Applied Bioorganic Chemistry, Gifu University, 1-1 Yanagido, Gifu-shi, Gifu 501-1193, Japan.

Published: May 2016

The convergent synthesis of the Lewis A (Le(a)) tandem repeat is described. The Le(a) tandem repeat is a carbohydrate ligand for a mannose binding protein that shows potent inhibitory activity against carcinoma growth. The Le(a) unit, {β-d-Gal-(1→3)-[α-l-Fuc-(1→4)]-β-d-GlcNAc}, was synthesized by stereoselective nitrile-assisted β-galactosylation with the phenyl 3-O-allyl-2,4,6-tri-O-benzyl-1-thio-β-galactoside, and ether-assisted α-fucosylation with fucosyl (N-phenyl)trifluoroacetimidate. This common Le(a) unit was easily converted to an acceptor and donor in high yields, and the stereoselective assembly of the hexasaccharide and dodecasaccharide as the Le(a) tandem repeat framework was achieved by 2-trichloroacetamido-assisted β-glycosylation and the (N-phenyl)trifluoroacetimidate method.

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Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6272916PMC
http://dx.doi.org/10.3390/molecules21050614DOI Listing

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