InChI=1S/C19H21NO7S/c1-20-18(22)17(21)15(12-6-4-3-5-7-12)16(19(20)26-2)13-8-10-14(11-9-13)27-28(23,24)25/h3-11,15-17,19,21H,1-2H3,(H,23,24,25)