Synthesis and analgesic activity evaluation of derivatives of 2-[(1,4-dioxo-1-amino-4-arylbutyl-2-en-2-yl)amino]-4,5,6,7-tetrahydrobenzo[<i>b</i>]thiophene-3-carboxylic acid

The synthesis of new derivatives 2-[(1,4-dioxo-1-amino-4-arylbutyl-2-en-2-yl)amino]-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carboxylic acid is described. Starting 2-{[5-aryl-2-oxofuran-3(2H)-ylidene]amino}thiophene-3-carboxylic acids were obtained by intramolecular cyclisation substituted 4-aryl-4-oxo-2-thienylaminobut-2-enoic in acetic anhydride. New via decyclization reaction acids. structure the compounds was confirmed 1H and 13C NMR spectroscopy, IR spectrometry elemental analysis methods. Analgesic activity has been studied “hot plate” method on outbred white mice both sexes with intraperitoneal injection. It found that possess analgesic effect exceeding comparison drug metamizole.