Showing structure for 3,7,14-trihydroxy-18,18-dimethyl-11-(3-methylbut-2-en-1-yl)-2,10,19-trioxapentacyclo[11.8.0.0³,¹¹.0⁴,⁹.0¹⁵,²⁰]henicosa-1(21),4,6,8,13,15(20),16-heptaen-12-one