Showing structure for {1,5,12,19-tetrahydroxy-7,18-dimethyl-3,14-dioxo-8,17-dioxapentacyclo[14.2.2.0²,¹⁵.0⁴,¹³.0⁶,¹¹]icosa-2(15),4(13),5,11-tetraen-9-yl}acetic acid