1H-Indazole-5-carbaldehyde (CAS NO.253801-04-6), its Synonyms are 1H-Indazole-5-carboxaldehyde (9CI) ; 6-[(4-Nitrophenyl)hydrazinylidene]hexane-1,2,3,4,5-pentol ; 6-[(4-Nitrophenyl)hydrazono]hexane-1,2,3,4,5-pentol .