A practical and highly stereoselective approach to access 2,6-disubstituted piperidines using an amidine auxiliary is reported. Following the diastereoselective addition of Grignard reagents at the 2-position of an activated pyridinium salt, the amidine group directs a regioselective metalation at the 6-position, enabling further functionalization. A subsequent electrophilic quench or a Negishi...

In this study, novel condensed 1,4-dihydropyridines bearing cyclopentanone (1-21) or tetrahydrothiophene-1,1-dioxide ring (22-42) with various ester substituents were synthesized via a modified Hantzsch reaction and their calcium channel modulator activities were investigated on isolated rat ileum and rat thoracic aorta. The introduction of a cyclopentanone ring fused to the 1,4-dihydropyridine...

Three types of calcium channels have been identified voltage-sensitive, receptor operated (cardiac muscle and vascular smooth muscle) and stretch operated (in some blood vessels) channels. Using electrophysiological and pharmacological techniques, three different types of voltage-gated calcium channels have been identified, namely, L-type (for long lasting, large channels), T–type (for transien...

OBJECTIVES Calcium-channel blockers have an important role in the treatment of several cardiovascular disorders. Derivatives of 1, 4-dihydropyridine are one of the most potent calcium antagonists. In this study four novel 1, 4-dihydropyridine calcium channel blockers were synthesized and their hypotensive properties were investigated in male rats. MATERIALS AND METHODS Four 1, 4-dihydropyridi...

The radiation-induced damage to mitochondrial oxidative respiratory chain could lead to generating of superoxide anions (O2-) and secondary reactive oxygen species (ROS), which are the major resources of continuous ROS production after radiation. Scavenging radiation-induced ROS effectively can help mitochondria to maintain their physiological function and relief cells from oxidative stress. Di...

Using the whole-cell configuration of the patch-clamp technique, we have characterized two types of ionic currents through voltage-dependent Ca2+ channels in human granulosa cells. One is long-lasting, activates at approximately -20 mV, reaches the peak at approximately +20 mV, has an inactivation time constant of 132.5 +/- 5.6 msec at 20 mV, and is sensitive to dihydropyridines. The other is t...

Cancer is a leading cause of death worldwide. Despite the availability of several chemotherapeutic drugs, there is still a great need for more efficient agents for a better management of cancer. In this contribution, a series of 11 1,4-dihydropyridines (1,4-DHPs) (4a, 4b and 7a-i) were synthesized and evaluated for their cytotoxic effect against MCF-7, LS180 and MOLT-4 cancer cell lines using M...