Stereoselectivity of NC-1100, a Ca-entry blocker

This lesson provides an in-depth discussion of the stereochemical outcomes in an SN1 reaction.
In the first step of an SN1 reaction, the bond between the electrophilic carbon and the leaving group ionizes to generate the carbocation intermediate. The second step of the mechanism is the nucleophilic attack.
In the formed carbocation, the positively charged carbon is sp2 hybridized with a trigonal planar geometry. As all the three substituents lie on the same plane, a plane of symmetry for the...

Adrenergic antagonists, or sympatholytics, inhibit adrenoceptor activation driven by catecholamines or agonists. Based on their adrenoceptor specificity, adrenergic blockers can be categorized into two primary groups: α-adrenergic blockers (α-blockers) and β-adrenergic blockers (β-blockers). α-blockers interact with α1 and α2 subtypes of α-adrenoceptors.
Nonselective α-blockers: Nonselective α-blockers contain haloalkylamine or imidazoline moieties. Phenoxybenzamine, with a haloalkylamine...

β-adrenergic antagonists, or β-blockers, modulate the sympathetic nervous system by targeting β-adrenoceptors and inhibiting catecholamine-mediated sympathetic responses. β-blockers differ in their adrenoceptor subtype affinity, lipophilicity, and α-blocking capabilities. The history of β-blocker development began with the prototype, dichloroisoprenaline, which exhibited partial agonist activity. As a result, propranolol was developed as a pure antagonist but nonselective agent, paving the way...

Nondepolarizing neuromuscular blockers induce paralysis by competitively blocking nicotinic acetylcholine receptors at the muscle end plate. Examples include pancuronium, mivacurium, vecuronium, and rocuronium. These quaternary ammonium derivatives are administered intravenously, are poorly absorbed, and are excreted via the kidneys.
Competitive antagonists prevent acetylcholine from binding to its receptor, inhibiting membrane depolarization. Without conformational changes or intrinsic...

All neuromuscular blocking agents are injected intravenously because they are poorly absorbed from the GI tract. Rapid onset is achieved with intravenous administration, although absorption is also adequate from an intramuscular injection. Since these agents are highly ionized, they do not readily penetrate cell membranes or cross the blood-brain barrier.
Instead, they are transported by the blood to different tissues. Muscles with a greater blood supply (arteries) and blood flow receive more...

Angina pectoris, a primary symptom of ischemic heart disease, requires careful pharmacological interventions. In this context, calcium channel blockers (CCBs) and ranolazine have emerged as crucial pharmacotherapeutic agents, providing deep insights into the complexities of angina management.
CCBs, a diverse class that includes dihydropyridines (nifedipine) and diphenylalkylamines (verapamil and diltiazem), exert their effect by blocking calcium channels in cardiac and smooth muscle cells. This...