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Pyridinium refers to the cation [C 5 H 5 NH] +. It is the conjugate acid of pyridine. Many related cations are known involving substituted pyridines, e.g. picolines ...
An ylide (/ ˈ ɪ l aɪ d /) [1] or ylid (/ ˈ ɪ l ɪ d /) is a neutral dipolar molecule containing a formally negatively charged atom (usually a carbanion) directly attached to a heteroatom with a formal positive charge (usually nitrogen, phosphorus or sulfur), and in which both atoms have full octets of electrons.
The first reaction is the formation of the N-2,4-dinitrophenyl-pyridinium salt (2). This salt is typically isolated and purified by recrystallization. The formation of the DNP-pyridinium salt. Upon heating a primary amine with the N-2,4-dinitrophenyl-pyridinium salt (2), the addition
Zincke aldehydes, or 5-aminopenta-2,4-dienals, are the product of the reaction of a pyridinium salt with two equivalents of any secondary amine, followed by basic hydrolysis. Using secondary amines (as opposed to primary amines) the Zincke reaction takes on a different shape forming Zincke aldehydes in which the pyridine ring is ring-opened ...
Radicals can propagate (k p) but also terminate (k t). However, persistent radicals (X), as stated above, cannot terminate with each other but only (reversibly) cross-couple with the growing species (k deact). Thus, every act of radical–radical termination is accompanied by the irreversible accumulation of X. Consequently, the concentration ...
The Kröhnke pyridine synthesis is reaction in organic synthesis between α-pyridinium methyl ketone salts and α, β-unsaturated carbonyl compounds used to generate highly functionalized pyridines. Pyridines occur widely in natural and synthetic products, so there is wide interest in routes for their synthesis.
Hydrogen abstraction from the 1’-deoxyribose carbon by the hydroxyl radical creates a 1 ‘-deoxyribosyl radical. The radical can then react with molecular oxygen, creating a peroxyl radical which can be reduced and dehydrated to yield a 2’-deoxyribonolactone and free base. A deoxyribonolactone is mutagenic and resistant to repair enzymes.
Deoxypyridinoline, also called D-Pyrilinks, Pyrilinks-D, or deoxyPYD, is one of two pyridinium cross-links that provide structural stiffness to type I collagen found in bones. [1] It is excreted unmetabolized in urine and is a specific marker of bone resorption and osteoclastic activity.