| 摘要 |
2-R-6-PY-3(2H)-pyridazinones (I) or salts thereof, which are useful as cardiotonics, where R is hydrogen, lower-alkyl or lower-hydroxyalkyl, and PY is 4- or 3-pyridinyl or 4- or 3-pyridinyl having one or two lower-alkyl substituents, are prepared by reacting 2-R-4,5-dihydro-6-PY-3(2H)-pyridazinone with a dehydrogenating agent. Also shown are: cardiotonic compositions and a method for increasing cardiac contractility using I or salts; and, the preparation of the corresponding intermediate 4,5-dihydro compounds. |
