InChI=1S/C17H20O9/c1-3-4-9-5-6-10(24-8(2)18)11(7-9)25-17-14(21)12(19)13(20)15(26-17)16(22)23/h3-7,12-15,17,19-21H,1-2H3,(H,22,23)/b4-3-