Novel Antiasthmatic Agents with Dual Activities of Thromboxane A₂ Synthetase Inhibition and Bronchodilation. V.Thienopyridazinone Derivatives

Abstract

Synthesis and pharmacological evaluation of novel thienopyridazinones and related compounds are described.A thiophene ring was found to be able to replace the benzene ring of a phthalazinone without loss of biological activities. This observation supports our hypothesis that the benzene ring plays an important role in both thromboxane A₂ (TXA₂) synthetase-inhibitory and bronchodilatory activities. Further, it was shown that the carbonyl moiety of a phthalazinone is not necessary for these activities.