Synonyms: Ambrosa-2,11(13)-dien-12-oicacid, 6a,8b-dihydroxy-4-oxo-, 12,8-lactone (8CI);Azuleno[6,5-b]furan-2,5-dione,3,3a,4,4a,7a,8,9,9a-octahydro-4-hydroxy-4a,8-dimethyl-3-methylene-, [3aS-(3aa,4a,4ab,7aa,8a,9aa)]-; Helenalin (6CI,7CI); (-)-Helenalin; Helenalin A; NSC 85236