Synthesis of 3-[(2,3-dihydro-1,1,3-trioxo-1,2-benzisothiazol-2-yl)alkyl] 1,4-dihydropyridine-3,5-dicarboxylate derivatives as calcium channel modulators

J Med Chem. 1992 Jun 26;35(13):2407-14. doi: 10.1021/jm00091a008.


1,4-Dihydropyridine (DHP) derivatives with a 1,2-benzisothiazol-3-one 1,1-dioxide group, linked through an alkylene bridge to the C-3 carboxylate of the DHP ring, with both vasoconstricting and vasorelaxant properties were obtained. In blocking Ca(2+)-evoked contractions of K(+)-depolarized rabbit aortic strips, compounds 12 and 41 were 10-fold more potent than nifedipine; 27 other compounds were 1-4-fold more potent. Their vascular versus cardiac selectivity was very pronounced; for instance, the selectivity index for compound 41 was 70-fold higher than that of nifedipine. This was also true for the vasoconstricting compound 22, which was as potent as Bay K 8644 in enhancing the Ca(2+)-evoked contractions of rabbit aorta strips, yet it had poor inotropic activity in rabbit left atria. Oral administration of compounds 38, 40, 43, and 53 (20 mg/kg) caused a 35-37% decrease in systolic blood pressure in spontaneously hypertensive rats (SHR); these effects were similar to those of nifedipine. However, iv administration of these compounds to anesthetized SHR caused a decrease in blood pressure which was more pronounced and long-lasting than that of nifedipine. When administered iv at 100 micrograms/kg, the vasoconstricting compound 22 caused a 40% increase in systolic and diastolic blood pressure. Compound 22 exhibited an unusually interesting feature over the other five Ca2+ DHP agonists: it had diester substitutions at the C-3 and C-5 positions of the DHP ring. Overall, compounds possessing these properties might be useful in treating clinical cardiovascular conditions in which DHP Ca2+ antagonists or agonists are indicated.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethyl-5-nitro-4-(2-(trifluoromethyl)phenyl)-, Methyl ester / pharmacology
  • Animals
  • Calcium / pharmacology
  • Calcium Channels / drug effects*
  • Cations
  • Dihydropyridines / chemical synthesis*
  • Dihydropyridines / pharmacology
  • Electric Stimulation
  • In Vitro Techniques
  • Male
  • Muscle Contraction / drug effects
  • Muscle, Smooth, Vascular / drug effects
  • Muscle, Smooth, Vascular / physiology
  • Potassium / pharmacology
  • Rabbits
  • Rats
  • Rats, Inbred Strains
  • Thiazoles / chemical synthesis*
  • Thiazoles / pharmacology


  • Calcium Channels
  • Cations
  • Dihydropyridines
  • Thiazoles
  • 3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethyl-5-nitro-4-(2-(trifluoromethyl)phenyl)-, Methyl ester
  • Potassium
  • Calcium