Showing structure for (1r,17r)-3,7,9-trihydroxy-1-methyl-16,21-dioxapentacyclo[15.3.1.0²,¹⁵.0⁴,¹³.0⁶,¹¹]henicosa-2,4(13),6,8,10,14-hexaene-5,12-dione