Synthesis and pharmacological evaluation of novel heterotricyclic acylhydrazone derivatives, designed as PAF antagonists

This paper describes the synthesis and the antiplatelet properties of new h eterotricyclic N-acylhydrazone derivatives (7a-e), structurally analogous t o known hetrazepinic PAF antagonists, exploring molecular hybridization as a tool for molecular designing. The synthetic route employed to access comp ounds (7a-e) used, as starting material, the previously described methyl 3- hydroxy-8-methyl-6-phenyl-6H-pyrazolo[3,4-b]thieno[2,3-d]pyridine-2-carboxy late derivative. The results from inhibitory effects of these: novel acylhy drazone derivatives (7a-e) upon PAF-induced platelet aggregation, indicated that all compounds present a significant antithrombotic profile. (C) 2000 Elsevier Science B.V. All rights reserved.