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Synthesis of nor-C-linked neuraminic acid disaccharide: a versatile precursor of C-analogs of oligosialic acids and gangliosides.

ABSTRACT: The Neu5Acalpha(2,8)Neu5Ac disaccharide is an important constituent of tumor related antigen, however, the O-linkage is catabolically unstable. Vaccination with a catabolically stable sialic acid C-glycoside analog might enhance immunogenicity. The synthesis of Neu5Ac nor-C-disaccharide 20R/S, corresponding to versatile precursors of C-analogs of oligosialic acid and gangliosides, is reported. The synthesis of the protected acceptor was not straightforward, as ester, silyl ether, and isopropylidene protection failed to afford desired C-linked disaccharide. Allyl ether protection of hydroxyl groups and acetyl protection of the acetamido facilitated the successful synthesis of the 8-aldehyde neuraminyl acceptor. Samarium mediated C-glycosylation afforded the desired nor-C-disaccharide as a mixture of two separable diastereomers.

SUBMITTER: Yuan X

PROVIDER: S-EPMC4129641 | biostudies-literature | 2007 Apr

REPOSITORIES: biostudies-literature

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Synthesis of nor-C-linked neuraminic acid disaccharide: a versatile precursor of C-analogs of oligosialic acids and gangliosides.

Yuan Xuejun X Ress Dino K DK Linhardt Robert J RJ

The Journal of organic chemistry 20070320 8

The Neu5Acalpha(2,8)Neu5Ac disaccharide is an important constituent of tumor related antigen, however, the O-linkage is catabolically unstable. Vaccination with a catabolically stable sialic acid C-glycoside analog might enhance immunogenicity. The synthesis of Neu5Ac nor-C-disaccharide 20R/S, corresponding to versatile precursors of C-analogs of oligosialic acid and gangliosides, is reported. The synthesis of the protected acceptor was not straightforward, as ester, silyl ether, and isopropylid ...[more]

PMID: 17371069

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