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 ct 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) (6 alpha H,7 alpha H,10 alpha methyl-eudesman-6,12-olide) Two different strategies were used, the first one an attempt to build the alpha-hydroxy-gamma-lactone moiety through functionalization of the C-6 position and the second involved the introduction of the C-ll hydroxyl group at the final steps of the synthetic scheme. (C) 2000 Elsevier Science Ltd. All rights reserved.