InChI=1S/C18H16O7/c1-9-7-12(20)15-13(8-9)25-18(17(22)23-3)11(16(15)21)5-4-6-14(18)24-10(2)19/h4-8,14,20H,1-3H3/t14-,18+/m1/s1