Synthesis and biological activity of new [1,3]Thiazolo[4,5-d]pyridazin-4(5H)-ones

Abstract

A series of novel 2-(N-pyrrolidino, N-piperidino or N-morpholino)-7-phenyl-(α-furoyl or α-thienyl)-[1,3]thiazolo[4,5-d]pyridazinones 10a–c, 14–16a,b was synthesized in 78–87% yields via the reaction of methyl 5-benzoyl(α-furoyl or α-thienyl)-2-aminosubstituted-thiazol-4-carboxylates 9a–c, 13a–e with hydrazine. These new compounds have been tested for their in vivo analgesic and anti-inflammatory activities. All compounds have been characterized by 1H-NMR, 13C-NMR spectroscopy, and liquid chromatography–mass spectrometry.