InChI=1S/C21H22O9/c22-9-17-18(25)19(26)20(27)21(30-17)28-12-5-6-13-14(24)8-15(29-16(13)7-12)10-1-3-11(23)4-2-10/h1-7,15,17-23,25-27H,8-9H2