InChI=1S/C21H20O9/c22-9-16-18(25)19(26)20(27)21(30-16)28-11-6-12(23)17-13(24)8-14(29-15(17)7-11)10-4-2-1-3-5-10/h1-8,16,18-23,25-27H,9H2/t16-,18-,19-,20-,21+/m0/s1