Synonyms: [3-[[5-(aminocarbonyl)-1-ethyl-1,6-dihydro-2-hydroxy-4-methyl-6-oxopyridin-3-yl]azo]phenyl]phosphonic acid;[3-[[[5-(Aminocarbonyl)-1-ethyl-1,6-dihydro-2-hydroxy-4-methyl-6-oxopyridin]-3-yl]azo]phenyl]phosphonic acid;1-Ethyl-1,2-dihydro-6-hydroxy-4-methyl-2-oxo-5-((3-phosphonophenyl)azo)-3-pyridinecarboxamide;Einecs 262-809-7;Phosphonic acid, (3-((5-(aminocarbonyl)-1-ethyl-1,6-dihydro-2-hydroxy-4-methyl-6-oxo-3-pyridinyl)azo)phenyl)-;Phosphonic acid, p-(3-(2-(5-(aminocarbonyl)-1-ethyl-1,6-dihydro-2-hydroxy-4-methyl-6-oxo-3-pyridinyl)diazenyl)phenyl)-