Total synthesis of (±)-jolkinolide A and B

Abstract

The first efficient synthesis of jolkinolide A and B from the diosphenol ( 7 ) is reported; the new synthetic method described may find use in the preparations of 4-ylidene-2,3-substituted butenolides. ~

Diterpenoids

“…The olefinic ester (149) that was used in the previous work was converted into the hydroxymethyl derivative (1 50) and thence into the unsaturat- J ed alkylated product (151). The lactone and ring A were then asassembled as in the previous strategy, via the propionate ester (152), the &lactone (153), and the aldehyde (154). The latter underwent an internal aldol condensation to form ring A.…”