| abstract |
This invention relates to therapeutic agents, which are new derivatives of phthalazine, and especially refers to these derivatives with a piperidine group substituted at position 1. The compounds of the invention are phosphodiesterase inhibitors and cardiac stimulants, of which a preferred class selectively increases the force of myocardial contraction without producing significant increases in heart rate. The compounds are useful in the curative or prophylactic treatment of cardiac conditions, such as congestive heart failure, angina, cardiac arrhythmias, and acute heart failure. |