InChI=1S/C21H19NO5/c1-21-12-3-4-13-18(26-9-23-13)17(12)20-22(2)19(21)11-7-15-14(24-8-25-15)5-10(11)6-16(21)27-20/h3-5,7,16,19-20H,6,8-9H2,1-2H3/t16-,19+,20-,21-/m0/s1