Showing structure for methyl 3-{17-hydroxy-8,9,10,14,18,18-hexamethyl-5-oxapentacyclo[11.8.0.0²,¹⁰.0⁴,⁹.0¹⁴,¹⁹]henicosa-1(13),2-dien-6-yl}-2-methylprop-2-enoate