Synthesis and in vitro pharmacology of new 1,4-dihydropyridines. 1. 2-(ω-Aminoalkylthiomethyl)-1,4-dihydropyridines as potent calcium channel blockers

The synthesis and in vitro calcium channel blocking activities and binding of 2-(ω- aminoalkylthiomethyl)-4-(substituted)phenyl-1,4-dihydropyridines, by determination of the displacement of [³H]nitrendipine from the calcium channel binding sites on rat cortex have been discussed. It has been shown that increasing the alkyl chain length on the 2-position of the 1,4-dihydropyridine ring from ethyl to pentyl does not affect the calcium channel blocking activity of 3-nitrophenyl substituted dihydropyridines, measured on K⁺-depolarisation induced contractile responses in rat aorta strips. It did not seem to be important whether the 1,4-dihydropyridines bore 2 identical or different ester moieties on the 3- and 5-position of the 1,4-dihydropyridine ring.