Showing structure for (3s,4ar,6ar,8s,10r,10ar,10bs)-3-ethenyl-3,4a,7,7,10a-pentamethyl-10-[(3-methylbut-2-enoyl)oxy]-5-oxo-octahydronaphtho[2,1-b]pyran-8-yl (2s,3r)-2,3-dimethyloxirane-2-carboxylate