(4aE,6R,7R,8S,14aS)-3-methoxy-6,7-dimethyl-1,2-dioxo-2,6,7,8-tetrahydro-1H-10,12,13-trioxabenzo[1,8]cycloocta[1,2,3-cd]-as-indacen-8-yl rel-(2Z)-2-methylbut-2-enoate 2-butenoic acid, 2-methyl-, (4aE,6R,7R,8S,14aS)-2,6,7,8-tetrahydro-3-methoxy-6,7-dimethyl-1,2-dioxo-1H,14H-10,12,13-trioxabenzo[1,8]cyclooct[1,2,3-cd]-as-indacen-8-yl ester, (2Z)- InChI=1/C26H26O8/c1-6-12(2)25(29)34-21-14(4)13(3)7-15-8-17(30-5)20(27)24(28)26(15)10-31-23-19(26)16(21)9-18-22(23)33-11-32-18/h6-9,13-14,21H,10-11H2,1-5H3/b12-6-,15-7+/t13-,14-,21?,26+/m1/s Interiotherin D