Showing structure for (5e,7r,8r,9r)-4-(2-methoxy-2-oxoacetyl)-5-(2-methoxy-2-oxoethylidene)-7,8-dimethyl-2,13,15-trioxatetracyclo[8.6.1.0⁴,¹⁷.0¹²,¹⁶]heptadeca-1(17),10,12(16)-trien-9-yl (2z)-2-methylbut-2-enoate