The synthesis of methyl O-α-L-rhamnopyranosyl-(1→2)-α-D-galactopyranosides specifically deoxygenated at position 2 (31), or 4 (21) of the rhamnopyranosyl residue was accomplished using methyl 3,4,6-tri-O-benzoyl-α-D-galactopyranoside (18) as the glycosyl acceptor. Phenyl thionocarbonate activation of the penta-O-benzoylated disaccharide precursor followed by Barton reduction and Zemplen transesterification gave 31, while 21 was obtained via condensation of the deoxygenated monosaccharide donor with 18, and subsequent debenzoylation of the product.
synthesis, O-antigen, O antigen, type, Shigella dysenteriae type 1, derivative, Shigella, disaccharide, Shigella dysenteriae, deoxygenated
NCBI PubMed ID: 7585707Journal NLM ID: 0043535Publisher: Elsevier
Institutions: NIDDK, National Institutes of Health, Bethesda, MD, USA
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