InChI=1S/C21H29NO7S/c23-21(22-13-12-18(15-22)29-30(24,25)26)9-7-5-3-1-2-4-6-8-17-10-11-19-20(14-17)28-16-27-19/h6,8,10-11,14,18H,1-5,7,9,12-13,15-16H2,(H,24,25,26)/b8-6+