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Macrocyclic bis-thioureas catalyze stereospecific glycosylation reactions.

ABSTRACT: Carbohydrates are involved in nearly all aspects of biochemistry, but their complex chemical structures present long-standing practical challenges to their synthesis. In particular, stereochemical outcomes in glycosylation reactions are highly dependent on the steric and electronic properties of coupling partners; thus, carbohydrate synthesis is not easily predictable. Here we report the discovery of a macrocyclic bis-thiourea derivative that catalyzes stereospecific invertive substitution pathways of glycosyl chlorides. The utility of the catalyst is demonstrated in the synthesis of trans-1,2-, cis-1,2-, and 2-deoxy-?-glycosides. Mechanistic studies are consistent with a cooperative mechanism in which an electrophile and a nucleophile are simultaneously activated to effect a stereospecific substitution reaction.

SUBMITTER: Park Y

PROVIDER: S-EPMC5671764 | biostudies-literature | 2017 Jan

REPOSITORIES: biostudies-literature

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Macrocyclic bis-thioureas catalyze stereospecific glycosylation reactions.

Park Yongho Y Harper Kaid C KC Kuhl Nadine N Kwan Eugene E EE Liu Richard Y RY Jacobsen Eric N EN

Science (New York, N.Y.) 20170101 6321

Carbohydrates are involved in nearly all aspects of biochemistry, but their complex chemical structures present long-standing practical challenges to their synthesis. In particular, stereochemical outcomes in glycosylation reactions are highly dependent on the steric and electronic properties of coupling partners; thus, carbohydrate synthesis is not easily predictable. Here we report the discovery of a macrocyclic bis-thiourea derivative that catalyzes stereospecific invertive substitution pathw ...[more]

PMID: 28082586

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