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

5-Substituted pyrrolo[1,2-b]pyridazines have been prepared by cyclisation of pyridazine with diphenylcyclopropenone followed by further functionalisations in the pyrrolo[1,2-b]pyridazine 5-position. Several compound exhibit profound inhibition of lipid peroxidation in vitro. Lipid peroxidation of boiled rat liver microsomes was induced by ascorbic acid/FeSO4 and the peroxidation was determined by measuring the thiobarbituric acid reactive material.