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

Synthesis of a new series of 4-aryl-1,4-dihydropyridines possessing potential calcium channel blocking activity along with good vasodilatory profile is reported. The compounds were synthesized using modified Hantzsch condensation of various aldehydes with methyl 3-aminocrotonate in the presence of a catalytic amount of trifluoroacetic acid and subsequent alkylation with various hydrochlorides of dialkylaminoalkyl chlorides. 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. Many compounds exhibited moderate to significant calcium channel blockade around 1 microM. The vasodilatory activity was assessed on isolated rat thoracic aortic rings precontracted by phenylephrine/KCl (30 mM). Most of the compounds produced a concentration-dependent inhibition of the contractile response.