InChI=1S/C13H16N2O7S/c1-2-9(8-16)12(13(17)18)7-14-23(21,22)11-5-3-10(4-6-11)15(19)20/h3-6,8-9,12,14H,2,7H2,1H3,(H,17,18)/t9-,12-/m1/s1