Synthesis of 2-(4-substitutedmethylpiperazin-1-yl)-N-(3,4-dihydro-3-oxo-2H-benzo[b][1,4]oxazin-7-yl)acetamides and their positive inotropic evaluation

A series of 2-(4-substitutedmethylpiperazin-1-yl)-N-(3,4-dihydro-3-oxo-2H-benzo[b][1,4]oxazin-7-yl)acetamides were synthesized and their positive inotropic activities were evaluated by measuring left atrium stroke volume on isolated rabbit heart preparations.