N,N"-(DITHIO-2,1-ETIIANEDIYL)BIS{N'-(PYRROL-2-YLMETI{YL)-1,6-HEXANEDIAMINE}(PYREXTRAMINE), A NEW IRREVERSIBLE a,.ADRENORECEPTOR BLOCKING AGENTTHE TETRAMINE DISULFIDE CLASS

In an attempt to further improve the a-adrenoreceptor blocking activity of benextramine, the effect of heteroaromaticsubstituents on the terminal nitrogens was studied. In this communication we report on the newly synthetizedN,N//-(dithio-2,1-ethanediyl)bis{N'-(pyrrol-2-ylmethyl)-1,6-hexanediamine} (pyrextramine) that displayed higher affinity(5-10-fold) and higher selectivity (about 12-fo1d) than benextramine. These preliminary results show thatpyrextramine can replace benextramine in the elucidation and characlerizatron of the peripheral ar-adrenoreceptors.