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Indium-mediated C-allylation of melibiose.

ABSTRACT: The indium-mediated allylation reaction has been applied to melibiose, a disaccharidic substrate. This elongation methodology allows for a short, efficient and diastereoselective approach towards complex glycosylated carbohydrate structures. The stereochemical outcome of the key intermediates, allylated disaccharides, has been determined by X-ray analysis. Ozonolysis of the introduced double bond yielded the unprotected elongated disaccharides in the equilibrium of the pyranoid as well as furanoid isomers in both anomeric forms, respectively. Per-O-acetylation has been performed to facilitate separation of the isomeric mixture for structural identification. The main product revealed to adopt a ?-pyranoid form of the elongated unit at the reducing end of the disaccharide.

SUBMITTER: Denner C

PROVIDER: S-EPMC6808214 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

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Indium-mediated C-allylation of melibiose.

Denner Christian C Gintner Manuel M Kählig Hanspeter H Schmid Walther W

Beilstein journal of organic chemistry 20191016

The indium-mediated allylation reaction has been applied to melibiose, a disaccharidic substrate. This elongation methodology allows for a short, efficient and diastereoselective approach towards complex glycosylated carbohydrate structures. The stereochemical outcome of the key intermediates, allylated disaccharides, has been determined by X-ray analysis. Ozonolysis of the introduced double bond yielded the unprotected elongated disaccharides in the equilibrium of the pyranoid as well as furano ...[more]

PMID: 31666880

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