Showing structure for 6-(furan-2-yl)-12,17-dihydroxy-1,5,11,16-tetramethyl-8-oxo-7,14-dioxapentacyclo[11.6.1.0²,¹¹.0⁵,¹⁰.0¹⁶,²⁰]icos-9-en-19-yl 2,3-dimethylbut-2-enoate