6-ethylsulfonyl-3-(4-methoxyphenyl)-[1,2,4]triazolo[3,4-a]phthalazine

6-chloro-3-phenyl-[1,2,4]triazolo[3,4-a]phthalazine

1-(4-chloro-phthalazin-1-yl)-3,5-diphenyl-formazan

N'-(4-chloro-phthalazin-1-yl)-benzohydrazonic acid N'-phenyl-hydrazide

6-ethoxytetrazolo[5,1-a]phthalazine