InChI=1S/C19H18O8/c1-5-7-8-9(12(21)11(5)20)13(22)15(24)14(23)10(8)16(25)19(26)17(7)27-6(2)18(19,3)4/h6,20,22-24,26H,1-4H3/t6-,19+/m0/s1