InChI=1S/C17H21NO7S/c19-17(18-9-3-5-14(11-18)25-26(20,21)22)6-2-1-4-13-7-8-15-16(10-13)24-12-23-15/h2,6-8,10,14H,1,3-5,9,11-12H2,(H,20,21,22)/b6-2+