Synonyms: Carda-4,20(22)-dienolide,11b,19-epoxy-14-hydroxy-11-methoxy-3-oxo-(7CI); Carda-4,20(22)-dienolide, 14,19-dihydroxy-3,11-dioxo-, 11,19-cyclicmethyl acetal (6CI); 5H-Cyclopenta[1,2]phenanthro[4,5-bcd]furan,carda-4,20(22)-dienolide deriv.; NSC 65944