title: Long-acting dihydropyridine calcium antagonists. 1. 2-Alkoxymethyl derivatives incorporating basic substituents.
abstract: A series of dihydropyridines substituted at the 2-position by basic side chains are described and their potencies as calcium antagonists listed. One compound, 2-[(2-aminoethoxy)methyl]-4-(2-chlorophenyl)-3-ethoxycarbonyl-5- methoxycarbonyl-6-methyl-1,4-dihydropyridine (17, amlodipine) was found to be comparable in potency to nifedipine and to have an elimination half-life of 30 h in dogs. Oral bioavailability approached 100%, and hemodynamic responses were gradual in onset and long-lasting in effect. The two enantiomers have been prepared, and the bulk of the activity was found to reside with the (-) isomer, 18. X-ray crystallographic studies, carried out on a close analogue of 17, suggest the existence of a weak hydrogen bond between the side-chain oxygen and the proton on the ring nitrogen.
mesh_terms: D017311:Amlodipine; D000818:Animals; D001681:Biological Assay; D001682:Biological Availability; D002121:Calcium Channel Blockers / Q000494:pharmacology*; D055598:Chemical Phenomena; D002621:Chemistry; D004095:Dihydropyridines; D004285:Dogs; D006168:Guinea Pigs; D006439:Hemodynamics / Q000187:drug effects; D007700:Kinetics; D008297:Male; D009543:Nifedipine / Q000031:analogs & derivatives / Q000378:metabolism / Q000494:pharmacology; D011725:Pyridines / Q000138:chemical synthesis / Q000378:metabolism / Q000494:pharmacology*; D051381:Rats; D014661:Vasoconstriction / Q000187:drug effects
chemical_list: D002121:Calcium Channel Blockers; D004095:Dihydropyridines; D011725:Pyridines; D017311:Amlodipine; C038806:1,4-dihydropyridine; D009543:Nifedipine