Showing structure for 13,17-dihydroxy-5-methoxy-7,12-dimethyl-9,15-dioxo-2,10,16-trioxatetracyclo[9.7.0.0³,⁸.0¹⁴,¹⁸]octadeca-1(11),3,5,7,12,14(18)-hexaene-4-carboxylic acid