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Asymmetric total syntheses of megacerotonic acid and shimobashiric acid A.

ABSTRACT: The asymmetric total syntheses of the ?-benzylidene-?-butyrolactone natural products megacerotonic acid and shimobashiric acid A have been accomplished in nine and 11 steps, respectively, from simple, commercially available starting materials. The key step for each synthesis is the (arene)RuCl(monosulfonamide)-catalyzed dynamic kinetic resolution-asymmetric transfer hydrogenation (DKR-ATH) of racemic ?,?-diketo-?-aryl esters to establish the absolute stereochemistry. Intramolecular diastereoselective Dieckmann cyclization forms the lactone core, and ketone reduction/alcohol elimination installs the ?-arylidene.

SUBMITTER: Krabbe SW

PROVIDER: S-EPMC4411184 | biostudies-literature | 2015 Mar

REPOSITORIES: biostudies-literature

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Asymmetric total syntheses of megacerotonic acid and shimobashiric acid A.

Krabbe Scott W SW Johnson Jeffrey S JS

Organic letters 20150220 5

The asymmetric total syntheses of the α-benzylidene-γ-butyrolactone natural products megacerotonic acid and shimobashiric acid A have been accomplished in nine and 11 steps, respectively, from simple, commercially available starting materials. The key step for each synthesis is the (arene)RuCl(monosulfonamide)-catalyzed dynamic kinetic resolution-asymmetric transfer hydrogenation (DKR-ATH) of racemic α,δ-diketo-β-aryl esters to establish the absolute stereochemistry. Intramolecular diastereosele ...[more]

PMID: 25699999

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