Synonyms: 1,4-Phthalazinedione,2,3-dihydro-, dihydrazone (9CI); Phthalazine, 1,4-dihydrazino- (7CI,8CI);1,4-Dihydrazinophthalazine; C 7441; Cassella 532; Dihydralazin; Dihydralazine;Dihydrazinophthalazine; Hypopresol; NSC 526654; Nepresol; Nepresolin;Nepressol; Ophthazin; Tonolysin