(5aS,6R,13aS,14R,17S,18R,19R,20S)-7,15-dihydroxy-1,3,9,11-tetramethoxy-17,20-bis(methoxymethoxy)-14-hydro-5H,6H-6,13a,5a,14-(epibutane[1,2,3,4]tetrayl)cycloocta[1,2-b:5,6-b']dinaphthalene-5,8,13,16-tetraone

(S)-3-(methoxymethoxy)octa-1,7-dien-3-one