1-Piperazineacetic acid, 4-(4-pyridinyl)-, (1,2-dihydro-2-oxo-3H-indol-3-ylidene)hydrazide 1-Piperazineacetic acid, 4-(4-pyridyl)-, (2-oxo-3-indolinylidene)hydrazide, (Z)- 4-(4-Pyridyl)-1-piperazineacetic acid cis-(2-oxo-3-indolinylidene)hydrazide 86889-04-5