β‐Selective C‐Glycosylation and its Application in the Synthesis of Scleropentaside A

C‐Glycosides are carbohydrates bearing a C−C bond to an aglycon at the anomeric center. Due to their high stability towards chemical and enzymatic hydrolysis, these compounds are widely used as carbohydrate mimics in drug development. Herein, we report a general and exclusively β selective method for the synthesis of a naturally abundant acyl‐C‐glycosidic structural motif found firstly in the Scleropentaside natural product family. A Corey‐Seebach Umpolung reaction as the key step in the synthesis of Scleropentaside A and analogues enables the β selective construction of the anomeric C−C bond starting from unprotected carbohydrates in only four steps. The methodology is highly atom‐ and pot‐efficient avoiding the use of toxic heavy metals.

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