Synonyms: 2-Butenoicacid, 3-methyl-,1a,2,3,7,8,8a,9,10,11a,11b-decahydro-1a-methyl-9-methylene-5,10-dioxo-5H-3,6-methenofuro[2,3-f]oxireno[d]oxacycloundecin-8-ylester, [1aR-(1aR*,3R*,8S*,8aR*,11aS*,11bR*)]-; Elephantin (7CI); Germacra-1(10),11(13)-diene-12,14-dioicacid, 4,5a-epoxy-2b,6a,8a-trihydroxy-, 12,6:14,2-dilactone, 3-methylcrotonate (8CI);5H-3,6-Methenofuro[2,3-f]oxireno[d]oxacycloundecin, 2-butenoic acid deriv.;Crotonic acid, 3-methyl-, 8-ester with 4,5a-epoxy-2b,6a,8a-trihydroxygermacra-1(10),11(13)-diene-12,14-dioicacid di-g-lactone (8CI); NSC 102817