Showing structure for {4-[(4-hydroxy-2-methylbut-2-enoyl)oxy]-3,6-dimethylidene-2-oxo-3ah,4h,5h,6ah,7h,9ah,9bh-azuleno[4,5-b]furan-9-yl}methyl 4-hydroxy-2-methylbut-2-enoate