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A convergent synthesis of the proposed structure of antitumor depsipeptide stereocalpin A.

ABSTRACT: The total synthesis of the proposed structure of anticancer agent stereocalpin A is described. The synthesis features a diastereoselective synthesis of a 5-hydroxy-2,4-dimethyl-3-oxooctanoic acid unit with asymmetric anti- and syn-aldol reactions as the key steps. Initial cycloamidation led to complete epimerization at the C-11 stereocenter due to unique steric constraints in the 12-membered depsipeptide ring. A late-stage methylation strategy led to the synthesis of the proposed structure of stereocalpin A.

SUBMITTER: Ghosh AK

PROVIDER: S-EPMC3179852 | biostudies-literature | 2009 May

REPOSITORIES: biostudies-literature

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A convergent synthesis of the proposed structure of antitumor depsipeptide stereocalpin A.

Ghosh Arun K AK Xu Chun-Xiao CX

Organic letters 20090501 9

The total synthesis of the proposed structure of anticancer agent stereocalpin A is described. The synthesis features a diastereoselective synthesis of a 5-hydroxy-2,4-dimethyl-3-oxooctanoic acid unit with asymmetric anti- and syn-aldol reactions as the key steps. Initial cycloamidation led to complete epimerization at the C-11 stereocenter due to unique steric constraints in the 12-membered depsipeptide ring. A late-stage methylation strategy led to the synthesis of the proposed structure of st ...[more]

PMID: 19354233

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