leptocarpin

(Z)-2-Methyl-2-butenoic acid [(1aR,3S,4Z,5aR,8aR,9R,10aR)-1a,2,3,5a,7,8,8a,9,10,10a-decahydro-3-hydroxy-4,10a-dimethyl-8-methylene-7-oxooxireno[5,6]cyclodeca[1,2-b]furan-9-yl] ester