InChI=1S/C21H22O10/c1-29-15-5-4-10(8-14(15)23)2-3-11-6-12(22)9-13(7-11)30-21-18(26)16(24)17(25)19(31-21)20(27)28/h2-9,16-19,21-26H,1H3,(H,27,28)/b3-2+