EIB eib [(3S,3aR,4R,6Z,9S,10E,11aR)-9-acetyloxy-6-(acetyloxymethyl)-3,10-dimethyl-2-oxidanylidene-3a,4,5,8,9,11a-hexahydro-3H-cyclodeca[b]furan-4-yl] (E)-2-methyl-4-oxidanyl-but-2-enoate EIB