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De novo asymmetric syntheses of SL0101 and its analogues via a palladium-catalyzed glycosylation.

ABSTRACT: The enantioselective syntheses of naturally occurring kaempferol glycoside SL0101 (1a) and its analogues 1b-e, as well as their enantiomers, have been achieved in 7-10 steps. The routes rely upon a diastereoselective palladium-catalyzed glycosylation, ketone reduction, and dihydroxylation to introduce the rhamno-stereochemistry. The asymmetry of the sugar moiety of these kaempferol glycosides was derived from Noyori reduction of an acylfuran. An acetyl group shift from an axial (C-2) to equatorial position (C-3) under basic conditions was also described. [reaction: see text]

SUBMITTER: Shan M

PROVIDER: S-EPMC2529254 | biostudies-literature | 2006 Oct

REPOSITORIES: biostudies-literature

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De novo asymmetric syntheses of SL0101 and its analogues via a palladium-catalyzed glycosylation.

Shan Mingde M O'Doherty George A GA

Organic letters 20061001 22

The enantioselective syntheses of naturally occurring kaempferol glycoside SL0101 (1a) and its analogues 1b-e, as well as their enantiomers, have been achieved in 7-10 steps. The routes rely upon a diastereoselective palladium-catalyzed glycosylation, ketone reduction, and dihydroxylation to introduce the rhamno-stereochemistry. The asymmetry of the sugar moiety of these kaempferol glycosides was derived from Noyori reduction of an acylfuran. An acetyl group shift from an axial (C-2) to equatori ...[more]

PMID: 17048865

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