InChI=1S/C21H22O10/c1-29-14-8-10(4-6-12(14)22)2-3-11-5-7-13(23)15(9-11)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+