InChI=1S/C21H29NO7S/c23-21(22-13-5-6-14-22)10-4-3-9-18(29-30(24,25)26)8-2-1-7-17-11-12-19-20(15-17)28-16-27-19/h1,7,11-12,15,18H,2-6,8-10,13-14,16H2,(H,24,25,26)/b7-1+