مشخصات پژوهش

The 1,4-dihydropyridine nucleus is a privileged scaffold since, when appropriately substituted, it can selectively modulate diverse receptors, channels and enzymes.1 Pyrazolopyridines and their derivatives have a wide range of biological activities.2-4 For example, a number of pyrazolo[3,4-b]pyridines exhibit anxiolytic (e.g., tracazolate), antiallergic, antiherpetic, antitubercular, antibacterial, antihypertensive and antifungal activities. In this work, in continuation of our interest in multicomponent reactions, we performed the three-component reaction of easily accessible 3-methyl-1H-pyrazol-5(4H)-one 1, ethyl 2- benzylidenacetoacetates 2 and ammonium acetate in refluxing ethanol, but dipyrazolo-1,4- dihydropyridine d. erivatives 3 were obtained instead of expected fused pyrazolo-1,4- dihydropyridines 4 (Scheme 1). The structure of synthesized compounds was confirmed by spectroscopic methods.