InChI=1S/C21H20N2O7/c24-15-16(25)18(20(27)28)30-19(17(15)26)22-21(29)23-13-7-3-1-5-11(13)9-10-12-6-2-4-8-14(12)23/h1-10,15-19,24-26H,(H,22,29)(H,27,28)/t15-,16-,17+,18-,19?/m0/s1