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Synthesis of partially O-acetylated N-acetylneuraminic acid using regioselective silyl exchange technology.

ABSTRACT: Postglycosylation acetylation of sialic acid imparts unique roles to sialoglycoconjugates in mammalian immune response making structural and functional understanding of these analogues important. Five partially O-acetylated Neu5Ac analogues have been synthesized. Reaction of per-O-silylated Neu5Ac ester with AcOH and Ac2O in pyridine promotes regioselective silyl ether/acetate exchange in the following order: C4 (2°) > C9 (1°) > C8 (2°) > C2 (anomeric). Subsequent hydrogenolysis affords the corresponding sialic acid analogues as useful chemical biology tools.

SUBMITTER: Park SS

PROVIDER: S-EPMC4184446 | biostudies-literature | 2014 Oct

REPOSITORIES: biostudies-literature

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Synthesis of partially O-acetylated N-acetylneuraminic acid using regioselective silyl exchange technology.

Park Simon S SS Gervay-Hague Jacquelyn J

Organic letters 20140923 19

Postglycosylation acetylation of sialic acid imparts unique roles to sialoglycoconjugates in mammalian immune response making structural and functional understanding of these analogues important. Five partially O-acetylated Neu5Ac analogues have been synthesized. Reaction of per-O-silylated Neu5Ac ester with AcOH and Ac2O in pyridine promotes regioselective silyl ether/acetate exchange in the following order: C4 (2°) > C9 (1°) > C8 (2°) > C2 (anomeric). Subsequent hydrogenolysis affords the corr ...[more]

PMID: 25247390

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