castelanone

2,16-Dioxo-11β,20-epoxypicrasa-3-ene-1β,11,12α,15β-tetrol 15-(3-methylbutanoate)

11β,20-Epoxy-1β,11,12α-trihydroxy-15β-(3-methyl-1-oxobutoxy)picras-3-ene-2,16-dione