Synthesis and anticonvulsant activity of some 1,4-dihydropyridine derivatives

A series of asymmetrical 4-alkyl/aryl-2,6-dimethyl-3-N-(aryl/heteroaryl)-carbamoyl-5-ethoxycarbonyl-1,4-dihydropyridines 3a-d and symmetrical 4-alkyl/aryl-2,6-dimethyl-3,5-bis-(ethoxycarbonyl)-1,4-dihydropyridines 4a and 4b have been prepared by the condensation of various benzaldehydes, ethylacetoacetate, 2-aminopyridine or p-toludine in ethanol (Hantzch method). The structures of all the synthesized 1,4-dihydropyridine derivatives have been confirmed by spectral data (IR, H-1 NMR) and elemental analysis. Compounds 3a-c, 4a and 4b (10 mg/kg) have been evaluated for their anticonvulsant effect against pentylenetetrazole- induced convulsions with phenytoin (4 mg/kg) as the standard. The anticonvulsant potential of the newly synthesized compounds have been assessed on the basis of increase in latency (onset time) to induce convulsions; decrease in number of convulsions and increase in latency of death compared to control and standard.