InChI=1S/C21H31NO8/c23-15(22-12-8-6-9-13-22)11-7-4-2-1-3-5-10-14-29-21-18(26)16(24)17(25)19(30-21)20(27)28/h1-4,8,12,16-19,21,24-26H,5-7,9-11,13-14H2,(H,27,28)/b3-1+,4-2-