Showing structure for (13s)-6,8,17,19-tetrahydroxy-14,14-dimethyl-18-(3-methylbut-2-en-1-yl)-3,15-dioxapentacyclo[11.6.1.0²,¹¹.0⁴,⁹.0¹⁶,²⁰]icosa-1(19),2(11),4,6,8,16(20),17-heptaen-10-one