InChI=1S/C15H14O7/c1-6-12-10(15(20,13(6)18)14(19)21-2)11(17)9-7(16)4-3-5-8(9)22-12/h3-6,10,12,16,20H,1-2H3/t6-,10+,12-,15-/m1/s1