Synthesis, evaluation of pharmacological activities and quantitative structure-activity relationship studies of a novel group of bis(4-nitroaryl-1,4-dihyropyridine).

Voltage-dependent calcium channels are crucial targets for a wide range of clinically active pharmacological agents. From these agents, 1,4-dihydropyridines constitute a group of small organic compounds are based on a core pyridine structure which can both block and enhance calcium currents. They are considered specific for L-Type calcium channels; however, other channel types, and in particular certain T-Type channels, may show sensitivity to dihydropyridine compounds. In this study, we synthesized a novel group of bis-1,4-dihydropyridines using the procedure reported by Dagnino that involved the condensation of n-alkyl diacetoacetate (n = 2-7) with methyl-3-aminocrotonate and nitrophenylaldehyde. The synthesis was run under two conditions: (i) reflux and (ii) microwave. Calcium channels antagonist activity were determined in vitro using guinea-pig ileum longitudinal smooth muscle assay. Synthesis of these compounds was confirmed with 1H-NMR, IR and mass spectrometry. Then IC(50) of them are calculated and compared with Nifedipine. Finally, the result of this pharmacological assay was used in quantitative structure-activity relationship studies utilizing multiple linear regression analysis. Most of these compounds are less active compared with Nifedipine. Decrease in activity is the result of increase in steric hindrance. The quantitative structure-activity relationship study indicates that the activity is related to the electrostatic and topological parameters and the distance between two C5-esteric groups of 1,4-dihydropyridine rings.