Showing structure for (8s,9s,10s)-3,4,5,19-tetramethoxy-9,10-dimethyl-15,17-dioxatetracyclo[10.7.0.0²,⁷.0¹⁴,¹⁸]nonadeca-1(12),2,4,6,13,18-hexaen-8-yl (2e)-2-methylbut-2-enoate