| abstract |
Process for the preparation of racemic 6-(4-amino-phenyl-5-methyl-pyridazin-3(2H)one of formula as an intermediate for obtaining optically substantially pure (-) enantiomer of [[4-(1,4,5,6-tetrahydro-4-methyl-6-oxo-3-pyridazinyl)phenyl] hydrazono]propanedinitrile. The pure enantiomer is useful as a cardiotonic agent, antihypertensive and vasodilator for the treatment of congestive heart failure. |