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Stereospecific Furanosylations Catalyzed by Bis-thiourea Hydrogen-Bond Donors.

ABSTRACT: We report a new method for stereoselective O-furanosylation reactions promoted by a precisely tailored bis-thiourea hydrogen-bond-donor catalyst. Furanosyl donors outfitted with an anomeric dialkylphosphate leaving group undergo substitution with high anomeric selectivity, providing access to the challenging 1,2-cis substitution pattern with a range of alcohol acceptors. A variety of stereochemically distinct, benzyl-protected glycosyl donors were engaged successfully as substrates. Mechanistic studies support a stereospecific mechanism in which rate-determining substitution occurs from a catalyst-donor resting-state complex.

SUBMITTER: Mayfield AB

PROVIDER: S-EPMC7293825 | biostudies-literature | 2020 Feb

REPOSITORIES: biostudies-literature

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Stereospecific Furanosylations Catalyzed by Bis-thiourea Hydrogen-Bond Donors.

Mayfield Andrew B AB Metternich Jan B JB Trotta Adam H AH Jacobsen Eric N EN

Journal of the American Chemical Society 20200214 8

We report a new method for stereoselective <i>O</i>-furanosylation reactions promoted by a precisely tailored bis-thiourea hydrogen-bond-donor catalyst. Furanosyl donors outfitted with an anomeric dialkylphosphate leaving group undergo substitution with high anomeric selectivity, providing access to the challenging 1,2-<i>cis</i> substitution pattern with a range of alcohol acceptors. A variety of stereochemically distinct, benzyl-protected glycosyl donors were engaged successfully as substrates ...[more]

PMID: 32013410

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