.alpha.-Aminopyridine .alpha.-Pyridinamine .alpha.-Pyridylamine .beta.-Pyridylamine 1,2-Dihydro-2-iminopyridine 2-Aminopryidine 2-Aminopyridine 2-Pyridinamine 2-Pyridylamine 504-29-0 NSC431 Pyridine, 2-amino- o-Aminopyridine