Showing structure for 5,9-dimethyl-5-[(2-methylbut-2-enoyl)oxy]-14-methylidene-4-oxo-3,11-dioxatetracyclo[7.5.0.0²,⁶.0¹⁰,¹²]tetradecan-13-yl 2-methylbut-2-enoate