Showing structure for 6-hydroxy-5a,9-dimethyl-4-[(2-methylbut-2-enoyl)oxy]-3-methylidene-2-oxo-3ah,4h,5h,6h,7h,9ah,9bh-naphtho[1,2-b]furan-5-yl 2,3-dimethyloxirane-2-carboxylate