Synonyms: 2H-1,11c-(Epoxymethano)phenanthro[10,1-bc]pyran-5,10(3H,6aH)-dione,1,3a,4,7,7a,11,11a,11b-octahydro-1a,2b,11b-trihydroxy-8,11ab-dimethyl-3-methylene- (8CI);Ailanthone (7CI);13,21-Didehydrochaparrinone;D13-Dehydrochaparrinone;(1β,11β,12α)-1,11,12-Trihydroxy-11,20-epoxypicrasa-3,13(21)-diene-2,16-dione;picrasa-3,13(21)-diene-2,16-dione, 11,20-epoxy-1,11,12-trihydroxy-, (1β,11β,12α)-;(1S,4R,5R,7S,11R,13S,17S,18S,19R)-4,5,17-trihydroxy-14,18-dimethyl-6-methylidene-3,10-dioxapentacyclo[9.8.0.01,7.04,19.013,18]nonadec-14-ene-9,16-dione;2H-1,11c-(Epoxymethano)phenanthro(10,1-bc)pyran-5,10(3H,6ah)-dione, 1,3a,4,7,7a,11,11a,11b-octahydro-8,11a-β-dimethyl-3-methylene-1-α,2-β,11-β-trihydroxy-;