7-hydroxy-12-oxidopyrido[3,2-a]phenazin-12-ium-5-one

1,2,4-benzotriazine

isoindolo[2,3-a]benzimidazol-11-one

8-nitro-1H-quinolin-4-one

2-ethyl-3-methyl-4-oxidoquinoxalin-1-ium 1-oxide