InChI=1S/C21H19ClO8/c1-8(7-23)4-5-11-9(2)18-13(6-12(11)24)29-19-14(21(28)30-18)10(3)16(22)17(25)15(19)20(26)27/h4,6,23-25H,5,7H2,1-3H3,(H,26,27)/b8-4+