InChI=1S/C22H16BrNO4/c23-18-8-4-5-9-20(18)28-17-12-10-15(11-13-17)14-19(22(26)27)24-21(25)16-6-2-1-3-7-16/h1-14H,(H,24,25)(H,26,27)/b19-14-