Studies on the Stereostructure of Eudesmanolides from Umbelliferae: Total Synthesis of (+)-Decipienin A

The first total synthesis of (+)-decipienin A has been achieved in 4% overall yield in seven steps from (+)-dihydrocarvone, thus confirming the stereostructure proposed by Holub et al. (Holub, M.; Budesinsky, M. Phytochemistry 1986, 25, 2015–2026) for this lactone and the original assignments should be corrected as indicated in by formula (a) (6αH,7αH,10αmethyl-eudesman-6,12-olide). Two different strategies were used, the first one an attempt to build the α-hydroxy-γ-lactone moiety through functionalization of the C-6 position and the second involved the introduction of the C-11 hydroxyl group at the final steps of the synthetic scheme.