InChI=1S/C18H18N2O7S/c1-20-7-8(16-19-5-6-28-16)11-9(20)3-2-4-10(11)26-18-14(23)12(21)13(22)15(27-18)17(24)25/h2-7,12-15,18,21-23H,1H3,(H,24,25)