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Synthesis of LewisX-O-Core-1 threonine: A building block for O-linked LewisX glycopeptides.

ABSTRACT: LewisX (LeX) is a branched trisaccharide Gal?1?4(Fuc?1?3)GlcNAc that is expressed on many cell surface glycoproteins and plays critical roles in innate and adaptive immune responses. However, efficient synthesis of glycopeptides bearing LeX remains a major limitation for structure-function studies of the LeX determinant. Here we report a total synthesis of a LeX pentasaccharide 1 using a regioselective 1-benzenesulfinyl piperidine/triflic anhydride promoted [3 + 2] glycosylation. The presence of an Fmoc-threonine amino acid facilitates incorporation of the pentasaccharide in solid phase peptide synthesis, providing a route to diverse O-linked LeX glycopeptides. The described approach is broadly applicable to the synthesis of a variety of complex glycopeptides containing O-linked LeX or sialyl LewisX (sLeX).

SUBMITTER: Sardar MYR

PROVIDER: S-EPMC5682196 | biostudies-literature | 2017 Nov

REPOSITORIES: biostudies-literature

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Synthesis of LewisX-O-Core-1 threonine: A building block for O-linked LewisX glycopeptides.

Sardar Mohammed Y R MYR Krishnamurthy Venkata R VR Park Simon S Mandhapati Appi Reddy AR Wever Walter J WJ Park Dayoung D Cummings Richard D RD Chaikof Elliot L EL

Carbohydrate research 20171010

LewisX (LeX) is a branched trisaccharide Galβ1→4(Fucα1→3)GlcNAc that is expressed on many cell surface glycoproteins and plays critical roles in innate and adaptive immune responses. However, efficient synthesis of glycopeptides bearing LeX remains a major limitation for structure-function studies of the LeX determinant. Here we report a total synthesis of a LeX pentasaccharide 1 using a regioselective 1-benzenesulfinyl piperidine/triflic an ...[more]

PMID: 29065342

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