Showing structure for (4as,5r,6s,8ar,9ar)-9a-[(4as,5r,6s,8ar,9ar)-3,4a,5-trimethyl-6-{[(2z)-2-methylbut-2-enoyl]oxy}-2-oxo-4h,5h,6h,7h,8h,8ah,9h-naphtho[2,3-b]furan-9a-yl]-3,4a,5-trimethyl-2-oxo-4h,5h,6h,7h,8h,8ah,9h-naphtho[2,3-b]furan-6-yl (2z)-2-methylbut-2-enoate