Showing structure for 12'-acetyl-10'-hydroxy-6,9'-dimethyl-4'-methylidene-5-(3-oxobut-1-en-1-yl)-4,6',9-trioxaspiro[tricyclo[6.3.0.0³,⁵]undecane-11,13'-tricyclo[8.4.0.0³,⁷]tetradecan]-11'-ene-5',10-dione