3-methoxy-16.17-seco-estrapentaene-(1.3.5.7.9)-dioic acid-(16.17)

methyl 7-methoxy-1-(2-methoxy-2-oxoethyl)-2-methyl-1,2,3,4-tetrahydrophenanthrene-2-carboxylate

Bis-dehydro-isomarrianolic acid methylether