InChI=1S/C16H20O8/c1-16(13(24-16)8-5-3-2-4-6-8)7-22-15-11(19)9(17)10(18)12(23-15)14(20)21/h2-6,9-13,15,17-19H,7H2,1H3,(H,20,21)