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Published on: February 7, 2019
Enantioselective total synthesis of callipeltoside A: two approaches to the macrolactone fragment
David A Evans1, Jason D Burch, Essa Hu
1Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford St., Cambridge, MA.
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.
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