Showing structure for methyl 15-(acetyloxy)-7-hydroxy-5,7,10,14,14-pentamethyl-4-methylidene-6,8,18-trioxo-19-oxapentacyclo[10.5.2.0¹,¹³.0²,¹⁰.0⁵,⁹]nonadec-2-ene-9-carboxylate