dihidropiridin

Dihydropyridine, often abbreviated as DHP, refers to a family of heterocyclic organic compounds derived from pyridine by partial saturation of the ring. The core structure is a six-membered ring containing one nitrogen atom and two saturated carbon atoms, giving a 1,4-dihydropyridine skeleton. Substituents can occupy positions around the ring, and the core can be further functionalized to yield a broad range of derivatives.

Chemically, dihydropyridines are typically described as partially saturated pyridines. They are relatively electron-rich due to the remaining double bonds in the ring, and their reactivity is influenced by substituents on the ring as well as the oxidation state of the ring system. The 1,4-dihydropyridine framework is a common scaffold in medicinal chemistry, in particular for calcium channel blockers.

Synthesis of 1,4-dihydropyridines is classically achieved by the Hantzsch reaction, a multicomponent condensation that combines an aldehyde, a β-ketoester, and ammonia (or ammonium acetate) to give 1,4-dihydropyridine products. Other methods include cyclizations from enaminones or related precursors. Because the ring can be oxidized to the fully unsaturated pyridine, dihydropyridines serve as convenient intermediates in organic synthesis for preparing pyridine-containing compounds.

Applications of dihydropyridines are diverse, but they are best known for their role as calcium channel blockers in medicine. DHP-based calcium channel blockers, such as nifedipine, amlodipine, felodipine, and nimodipine, are used to treat hypertension and angina. The substituent patterns on the dihydropyridine core strongly influence pharmacological activity and selectivity, making this scaffold a focal point in drug discovery and development.