Synonyms: 2-Butenoicacid, 2-methyl-,6-(acetyloxy)-2,3,3a,4,5,6,6a,7,8,9b-decahydro-3,3a-dihydroxy-3,6,9-trimethyl-4-(2-methyl-1-oxobutoxy)-7-(3-methyl-1-oxobutoxy)-2-oxoazuleno[4,5-b]furan-8-ylester (9CI); Azuleno[4,5-b]furan, 2-butenoic acid deriv.; Thapsitranstagin