Synthesis and smooth muscle calcium channel antagonist effects of dialkyl 1,4-dihydro-2,6-dimethyl-4-aryl-3,5-pyridinedicarboxylates containing a nitrooxy or nitrophenyl moiety in the 3-alkyl ester substituent

Nitric oxide releasing morpholine derivatives as hypolipidemic and antioxidant agents

The synthesis and evaluation of activity of some nitric acid esters of substituted morpholines are presented. All compounds inhibit lipid peroxidation and reduce cholesterol (20-63%) and triglyceride (37-85%) plasma levels. The more potent NO donors 14 and 17 specifically reduce low-density lipoprotein (LDL). These data indicate that proper structural modifications to the hypolipidemic and antioxidant morpholines enabling NO production, besides preserving or enhancing the above activities, offer a remarkable reduction of LDL, considered advantageous for antiatheromatic agents.

Synthesis and calcium channel antagonist activities of 3-nitrooxyalkyl, 5-alkyl 1,4-dihydro-2,6-dimethyl-4-(1-methyl-5-nitro-2-imidazolyl)-3, 5-pyridinedicarboxylates

A group of racemic 3-[(2-nitrooxyethyl), (3-nitrooxypropyl), (4-nitrooxybutyl) or (1,3-dinitrooxy-2-propyl)], 5-methyl (ethyl or propyl) 1,4-dihydro-2,6-dimethyl-4-(1-methyl-5-nitro-2-imidazolyl)-3,5-pyridinedicarboxylates (18-29) were synthesized using modified Hantzsch reaction that involved the condensation of 2-nitrooxyethyl (8), 3-nitrooxypropyl (9), 4-nitrooxybutyl (10) or 1,3-dinitrooxy-2-propyl (13) acetoacetate with methyl (14), ethyl (15) or isopropyl (16) 3-aminocrotonate and 1-methyl-5-nitroimidazole-2-carboxaldehyde (17). In vitro calcium channel antagonist activities were determined using a guinea pig ileum longitudinal smooth muscle assay. Compounds 18-29 exhibited superior, or equipotent, calcium antagonist activity (IC50= 10(11) - 10(-13) M range) relative to the reference drug nifedipine (IC50 = 1.07 +/- 0.12 x 10(-11) M), which could serve as potential probes to investigate the in vivo release of nitric oxide which induces vascular muscle relaxation.

Design and synthesis of substituted compounds containing the 1, 4-benzodioxin subunit. New potential calcium antagonists

New compounds possessing 1,4-benzodioxin or its saturated analogous heterocyclic system were synthesized and tested for calcium antagonist activity. Biological differences were seen between the different modifications applied. These compounds have been shown to be representative of a novel series of calcium channel antagonists.

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

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.

New substituted 1,4-benzoxazine derivatives with potential intracellular calcium activity

Substituted 1,4-benzoxazines bearing an amino side chain at the 2-position were prepared and were found to have a moderate activity on intracellular calcium. Of the compounds studied it was found that those which possess a homoveratrylamino moiety exhibited superior potency. The chain length and the nature of the amine (4-fluorophenylpiperazine, 4-fluorobenzhydryloxyethylamine, N-substituted homoveratrylamine) is discussed. The 4-benzyl-3, 4-dihydro-2-[3-[[2-(3,4-dimethoxyphenyl)ethyl]amino]propyl]-2H-1, 4-benzoxazine (3c) is the most potent derivative of the series with a ratio of IC50 values against PE (phenylephrine) and K+ of 2.1. Under these test conditions a ratio near 1 indicates potential intracellular calcium activity while a ratio greater than 100 an action on extracellular calcium influx.