2,3-dioxo-6-nitro-7-sulfamoylbenzo(f)quinoxaline [ 2,3-dihydroxy-6-nitro-7-sulfamoyl-benzo(f)quinoxaline,6-nitro-7-sulfamoylbenzo(f)quinoxaline-2,3-dione,FG 9202,FG-9202,NBQX ] structure given in first source; neuroprotectant for cerebral ischemia; AMPA receptor antagonist