1,4-Dihydro-1-(4-hydroxyphenyl)-4-oxo-2,6-pyridinedicarboxylic acid dihydrazide 1-(p-Hydroxyphenyl)chelidamic acid dihydrazide 2,6-Pyridinedicarboxylic acid, 1,4-dihydro-1-(4-hydroxyphenyl)-4-oxo-, dihydrazide 97941-97-4 BRN 5992456