Showing structure for 1-hydroxy-9,9,18-trimethyl-18-[2-methyl-3-(4-methyl-5-oxofuran-2-ylidene)propanoyl]-4,8,15-trioxapentacyclo[11.7.0.0³,⁷.0³,¹⁰.0¹⁴,¹⁹]icosane-5,16-dione