2,9-dihydro-(6 or 7)-(3-oxo-2,3,4,5-tetrahydropyridazinyl)-pyrazolo [4,3-B]-1,4-benzoxazines

摘要

The invention relates to novel compounds, 2,9-dihydro(6 or 7)-3-oxo-2,3,4,5-tetrahydropyridazinyl)pyrazolo[4,3-b]benzoxazines. The claimed compounds are inhibitors of phosphodiesterase fraction III and have potent positive inotropic activity. These compounds are useful as cardiotonics or platelet aggregation inhibitors. This invention also pertains to compositions comprising an effective amount of the compounds, to methods for preparing the claimed compounds and to methods for treating a mammal with the compounds.