1-hydroxy-5-oxo-5H-pyrido[3,2-a]-phenoxazine-3-carboxylic acid, Pirenoxina [Spanish], Catalin, 1,5-dioxo-1,5-dihydro-4H-pyrido[3,2-a]phenoxazine-3-carboxylic acid, pirenoxine, Pirenoxinum, Catalin-K (TN), Pirenoxina, pirfenoxone, 1-Hydroxy-pyrido-5-phenoxazon-3-carbonsaeure, Pirenoxinum [Latin]