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Exploration of cascade cyclizations terminated by tandem aromatic substitution: total synthesis of (+)-schweinfurthin A.

ABSTRACT: The termination of epoxide-initiated cascade cyclizations with a range of "protected" phenols is described. When the protecting group can be lost as a stabilized electrophile, the cascade process continues beyond ring closure to afford products which have undergone a tandem electrophilic aromatic substitution. A number of groups have proven viable in this process and the regiochemistry of their substitution reactions has been studied. Application of this methodology in the first total synthesis of (+)-schweinfurthin A, a potent antiproliferative agent, has been achieved.

SUBMITTER: Topczewski JJ

PROVIDER: S-EPMC3069933 | biostudies-literature | 2011 Feb

REPOSITORIES: biostudies-literature

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Exploration of cascade cyclizations terminated by tandem aromatic substitution: total synthesis of (+)-schweinfurthin A.

Topczewski Joseph J JJ Kodet John G JG Wiemer David F DF

The Journal of organic chemistry 20110112 3

The termination of epoxide-initiated cascade cyclizations with a range of "protected" phenols is described. When the protecting group can be lost as a stabilized electrophile, the cascade process continues beyond ring closure to afford products which have undergone a tandem electrophilic aromatic substitution. A number of groups have proven viable in this process and the regiochemistry of their substitution reactions has been studied. Application of this methodology in the first total synthesis ...[more]

PMID: 21226493

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