2-Butenoic acid, 2-methyl-, 2,3,3a,4,5,6,7,11-octahydro-10-(hydroxymethyl)-6-methyl-3-methylene-2,7-dioxo-6,9-epoxycyclodeca(b)furan-4-yl ester, (3aR-(3aR*,4R*(Z),6R*,10Z,11aR))- 59481-48-0