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Enantioselective total synthesis of callipeltoside A: two approaches to the macrolactone fragment.

ABSTRACT: The enantioselective total synthesis of callipeltoside A is described. Two syntheses of the macrolactone subunit are included: the first relies upon an Ireland-Claisen rearrangement to generate the trisubstituted olefin geometry and the second utilizes an enantioselective vinylogous aldol reaction for this purpose. Enantioselective syntheses of the sugar and chlorocyclopropane side chain fragments are also disclosed. The relative and absolute stereochemistry of this natural product was determined by fragment coupling with the two enantiomers of the side chain fragment.

SUBMITTER: Evans DA

PROVIDER: S-EPMC3408859 | biostudies-literature | 2008 May

REPOSITORIES: biostudies-literature

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Enantioselective total synthesis of callipeltoside A: two approaches to the macrolactone fragment.

Evans David A DA Burch Jason D JD Hu Essa E Jaeschke Georg G

Tetrahedron 20080501 21

The enantioselective total synthesis of callipeltoside A is described. Two syntheses of the macrolactone subunit are included: the first relies upon an Ireland-Claisen rearrangement to generate the trisubstituted olefin geometry and the second utilizes an enantioselective vinylogous aldol reaction for this purpose. Enantioselective syntheses of the sugar and chlorocyclopropane side chain fragments are also disclosed. The relative and absolute stereochemistry of this natural product was determine ...[more]

PMID: 22859865

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