InChI=1S/C21H29NO7S/c23-21(22-13-5-6-14-22)12-10-18(29-30(24,25)26)8-4-2-1-3-7-17-9-11-19-20(15-17)28-16-27-19/h3,7,9,11,15,18H,1-2,4-6,8,10,12-14,16H2,(H,24,25,26)/b7-3+