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Concise total syntheses of aspalathin and nothofagin.

ABSTRACT: Syntheses of the C-glycosyl flavone natural products aspalathin and nothofagin have been accomplished in eight steps from tribenzyl glucal, tribenzylphloroglucinol, and either 4-(benzyloxy)phenylacetylene or 3,4-bis(benzyloxy)phenylacetylene. The key step of the syntheses involves a highly stereoselective Lewis acid promoted coupling of 1,2-di-O-acyl-3,4,6-tribenzylglucose with tribenzylphloroglucinol, which gives rise to the corresponding beta-C-aryl glycoside in 30-65% yields.

SUBMITTER: Yepremyan A

PROVIDER: S-EPMC2859843 | biostudies-literature | 2010 Apr

REPOSITORIES: biostudies-literature

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Concise total syntheses of aspalathin and nothofagin.

Yepremyan Akop A Salehani Baback B Minehan Thomas G TG

Organic letters 20100401 7

Syntheses of the C-glycosyl flavone natural products aspalathin and nothofagin have been accomplished in eight steps from tribenzyl glucal, tribenzylphloroglucinol, and either 4-(benzyloxy)phenylacetylene or 3,4-bis(benzyloxy)phenylacetylene. The key step of the syntheses involves a highly stereoselective Lewis acid promoted coupling of 1,2-di-O-acyl-3,4,6-tribenzylglucose with tribenzylphloroglucinol, which gives rise to the corresponding beta-C-aryl glycoside in 30-65% yields. ...[more]

PMID: 20222686

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