Synonyms: 2-Butenoicacid, 2-methyl-,4-(acetyloxy)-2,3,3a,4,5,6,7,10,11,11a-decahydro-6-hydroxy-6,10-dimethyl-3-methylene-2,7-dioxocyclodeca[b]furan-5-ylester, [3aS-[3aR*,4R*,5S*(Z),6S*,8Z,10S*,11aS*]]-; Cyclodeca[b]furan,2-butenoic acid deriv.; Calein B