Synthesis of a new series of 4-Aryl-1,4-dihydropyridines with calcium channel blocking and vasodilatory activity

Several new amide derivatives of 4-aryl-1, 4-dihydropyridine carboxylic congeners have been synthesized in this study to obtain therapeutically useful compounds. The changes in pharmacological properties of dihydropyridines by the presence of polar groups at different positions of 4-phenyl substituent and also by introduction of unsymmetrical ester groups in the synthesized symmetrical analogs have been studied. In vitro calcium channel blocking activity has been evaluated in cultures of neonatal rat cortical neurons by measuring the inhibitory response at L-type calcium channels activated by veratridine. The newly synthesized dihydropyridines displayed moderate calcium channel blockade with IC values ranging from 2 to 10 μM in comparison to nifedipine (IC = 57.7 nM). The vasodilatory activity was evaluated on isolated rat thoracic aortic rings precontracted by phenylephrine/KCl (30 mM). The symmetrically substituted dihydropyridine 8a exhibited maximum activity with IC = 0.64 μMbut was found to be approximately 24 times less active in comparison to standard drug nifedipine with IC = 27.5 nM. © Springer Science+Business Media, LLC 2011