InChI=1S/C20H26O7/c1-9-6-7-13(21)18(4)8-12(25-17(23)19(5)11(3)27-19)14-10(2)16(22)26-15(14)20(9,18)24/h11-15,21,24H,1-2,6-8H2,3-5H3