InChI=1S/C13H17NO7S/c1-9-8-10(20-13(9)16)4-2-3-6-14-7-5-11(12(14)15)21-22(17,18)19/h4,8,11H,2-3,5-7H2,1H3,(H,17,18,19)/b10-4+