Synthesis of 5-substituted pyrrolo[1,2-b]pyridazines with antioxidant properties

5-Substituted pyrrolo[1,2-b]pyridazines have been prepared by cyclisation o f pyridazine with diphenylcyclopropenone followed by further functionalisat ions in the pyrrolo[1,2-b]pyridazine 5-position. Several compound exhibit p rofound inhibition of lipid peroxidation in vitro. Lipid peroxidation of bo iled rat liver microsomes was induced by ascorbic acid/FeSO4 and the peroxi dation was determined by measuring the thiobarbituric acid reactive materia l.