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Stereoselective synthesis of both tetrahydropyran rings of the antitumor macrolide, (-)-lasonolide A.

ABSTRACT: Stereoselective syntheses of both functionalized tetrahydropyran subunits of (-)-lasonolide A are described. These tetrahydropyran rings were constructed using catalytic asymmetric hetero Diels-Alder reactions as the key steps. The C22 quaternary stereocenter present in the upper tetrahydropyran ring was constructed by a stereoselective alkylation, and the C9 hydroxy stereochemistry of the bottom tetrahydropyran was constructed by a stereoselective epoxidation followed by a regioselective epoxide opening reaction.

SUBMITTER: Ghosh AK

PROVIDER: S-EPMC3292631 | biostudies-literature | 2012 Mar

REPOSITORIES: biostudies-literature

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Stereoselective synthesis of both tetrahydropyran rings of the antitumor macrolide, (-)-lasonolide A.

Ghosh Arun K AK Ren Guo-Bao GB

The Journal of organic chemistry 20120210 5

Stereoselective syntheses of both functionalized tetrahydropyran subunits of (-)-lasonolide A are described. These tetrahydropyran rings were constructed using catalytic asymmetric hetero Diels-Alder reactions as the key steps. The C22 quaternary stereocenter present in the upper tetrahydropyran ring was constructed by a stereoselective alkylation, and the C9 hydroxy stereochemistry of the bottom tetrahydropyran was constructed by a stereoselective epoxidation followed by a regioselective epoxid ...[more]

PMID: 22324913

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