InChI=1S/C21H22O9/c22-9-17-18(25)19(26)20(27)21(30-17)28-12-4-1-10(2-5-12)15-8-14(24)13-6-3-11(23)7-16(13)29-15/h1-7,15,17-23,25-27H,8-9H2/t15?,17-,18-,19+,20-,21-/m1/s1