1,2-Dihydro-1,5-dimethyl-4-(methylnitrosoamino)-2-phenyl-3H-pyrazol-3-one 3H-Pyrazol-3-one, 1,2-dihydro-1,5-dimethyl-4-(methylnitrosoamino)-2-phenyl- 4-(N-Methyl-N-nitroso)aminoantipyrine 4-Nitroso-N-methylaminoantipyrine 73829-38-6 Antipyrine, 4-(methylnitrosamino)- BRN 5570711 MNAA