Syntheses, Calcium Channel Agonist−Antagonist Modulation Activities, Nitric Oxide Release, and Voltage-Clamp Studies of 2-Nitrooxyethyl 1,4-Dihydro- 2,6-dimethyl-3-nitro-4-(2-trifluoromethylphenyl)pyridine-5-carboxylate Enantiomers
摘要:
The novel (-)-(S)-2 and (+)-(R)-3 enantiomers of 2-nitrooxyethyl 1,4-dihydro-2,6-dimethyl-3nitro-4-(2-trifluoromethylphenyl)pyridine-5-carboxylate were synthesized for evaluation as calcium channel modulators. Determination of their in vitro calcium-channel-modulating activities using guinea pig left atria (GPLA) and ileum longitudinal smooth muscle (GPILSM) showed that the (-)-(S)-2 enantiomer acted as a dual cardioselective calcium channel agonist (GPLA)/smooth muscle selective calcium channel antagonist (GPILSM). In contrast, the (+)(R)-3 enantiomer exhibited calcium channel antagonist activity on both GPLA and GPILSM. The 2-nitrooxyethyl racemate is a nitric oxide ((NO)-N-.) donor that released 2.7% (NO)-N-., relative to the reference drug glyceryl trinitrate (5.3% (NO)-N-. release/ONO2 moiety), in the presence of N-acetylcysteamine. Whole-cell voltage-clamp studies using isolated guinea pig ventricular myocytes indicated that both enantiomers inhibit calcium current but that the (-)-(S)-2 enantiomer is a weaker antagonist than the (+)-(R)-3 enantiomer. These results indicate that replacement of the methyl ester substituent of (-)-(S)-methyl 1,4-dihydro-2,6-dimetyl-3-nitro4-(2-trifluoromethylphenyl)pyridine-5-carboxylate [(-)-(S)-1] by the 2-nitrooxyethyl ester (NO)-N-. donor substituent present in (-)-(S)-2 provides a useful drug design concept to abolish the contraindicated calcium channel agonist effect of (-)-(S)-1 on vascular smooth muscle. The novel (-)-(S)-2 enantiomer is a useful lead compound for drug discovery targeted toward the treatment of congestive heart failure, and it provides a useful probe to study the structure-function relationships of calcium channels.
The design of (−)-(S)-2-nitrooxyethyl 1,4-dihydro-2,6-dimethyl-3-nitro-4-(2-trifluoromethylphenyl)Pyridine-5-carboxylate: A cardioselective positive inotropic derivative of bay K 8644
摘要:
The title compound, (-)-(S)-9, is a novel cardioselective calcium channel modulator that exhibits a calcium channel agonist effect on heart, a weak calcium channel antagonist effect on smooth muscle, and releases nitric oxide in vitro. (-)-(S)-9 is a useful lead-compound for the design of positive inotropic agents to treat congestive heart failure, and to study the structure-function relationship of calcium channel modulation. (C) 1999 Elsevier Science Ltd. Ail rights reserved.