Showing structure for (3ar,4s,6s,8s,8as,9ar)-6-(acetyloxy)-5-[(acetyloxy)methyl]-8-hydroxy-8a-methyl-3-methylidene-2-oxo-3ah,4h,6h,7h,8h,9h,9ah-naphtho[2,3-b]furan-4-yl (2e)-2-methylbut-2-enoate