Synthesis and structural affirmation of the a marine alkaloid lysiformine is reported.
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A synthesis of the bisindole alkaloid lysiformine is reported. The heterocyclic skeleton of the ...natural product was assembled from a kojic acid-derived pyridine using iterative Suzuki coupling and reductive alkylation reactions. The NMR spectroscopic data of the synthetic sample was in excellent agreement to the natural product, confirming that lysiformine is a rare example of a marine natural product harbouring a 3-hydroxypyridine.
3-Hydroxypyridinium and 3-(hydroxymethyl)pyridinium O-terpenyl aryldithiophosphonates were obtained by the reactions of 3-hydroxypyridine and 3-(hydroxymethyl)pyridine with O-terpenyl ...aryldithiophosphonic acids on the basis of (1R,2S,5R)-(−)-menthol, (1S)-endo-(–)-borneol, racemic isoborneol, and carvacrol. The obtained salts possess high antimicrobial activity against Bacillus cereus and Candida albicans.
An efficient and practical organocatalytic system comprising 3-hydroxypyridine and tetra-n-butylammonium iodide was developed for the synthesis of cyclic carbonates from carbon dioxide and epoxides ...under mild conditions (1 atm CO2, 25–60 °C) without organic solvent. By comparing with related hydroxypyridine derivatives, the effects of the hydroxyl group, the acidity and the steric factor, were discussed. Study on the mixtures of CO2 and N2 in various ratios indicated that the yield depends on CO2 content, due to the solubility of CO2 in the reaction mixture. The system was also shown not to be deteorated by the presence of H2O, air or O2.
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•Formation pathways of 2-alkyl-3-hydroxypyridines in foods are described.•Main precursors resulted to be 4,5-epoxy-2-alkenals and 2,4-alkadienals.•Hydroxypyridines are produced by cyclization of ...precursors induced by ammonia.•Hydroxypyridines are formed when oxidized oils are heated with ammonia.•Hydroxypyridines are generated as a consequence of the lipid oxidation pathway.
Pyridines are produced during food processing and are important flavor compounds. In spite of that, their formation pathways are still poorly understood, in particular those related to 3-hydroxypyridines. In an attempt to fill this gap, this study describes, for the first time, precursors and reaction pathways leading to 3-hydroxypyridine formation. 3-Hydroxypyridines are produced by reaction of lipid-derived reactive carbonyls and ammonia-producing compounds and were studied by using gas chromatography coupled to mass spectrometry. Their main precursors resulted to be 4,5-epoxy-2-alkenals and 2,4-alkadienals. 3-Hydroxypyridines were produced at temperatures higher than 100 °C, at slightly basic pH values, and with an activation energy of about 50 kJ/mol. A reaction pathway that explains their formation in the course of the lipid oxidation pathway is proposed. The role of lipid oxidation on the production of 3-hydroxypyridines was confirmed by studying their formation in oxidized linseed and menhaden oils heated in the presence of glutamine.
The synthesis and structural characterization of two new complexes catena-Ni(3-O-py)(3-HO-py)2(μ1,3-N3)(H2O) (1) and catena-Zn(μ-3-O-py)(μ1,1-N3) (2), where 3-HO-py = 3-hydroxypyridine, are reported. ...The complexes were characterized by the elemental microanalyses, IR, and X-ray crystallography and by UV–Vis spectroscopy for complex 1. Single crystal X-ray crystallography revealed the polymeric nature of the complexes: 1 as 1D with a single EE azide bridging, and 2 as 2D with μ(O,O′,N) bridging of the deprotonated 3-O-py anions and di-EO azide groups, respectively. In 1 the neutral and deprotonated 3-hydroxypyridine molecules act only as N-terminal ligands. The emission spectral properties of the Zn(II) complex were investigated.
The synthesis and characterization of 1-D catena-Ni(3-O-py)(3-OH-py)2(μ1,3-N3)(H2O) (1) and 2-D catena-Zn(μ-3-O-py)(μ1,1-N3) (2), (3-OH-py = 3-hydroxypyridine) are reported. Display omitted
•Polymeric azido Ni(II) and Zn(II) complexes based on 3-hydroxypyridine were structurally characterized.•Single end-to-end azide bridges connect the NI(II) centers of the 1-D system of 1.•The 2-D system of 2 is formed by di-EO azide and anionic μ(O,O′,N) 3-O-py bridging ligands.•Luminescent properties of 2 are reported.
Since coffee is a significant contributor to the consumption of acrylamide, its reduction is required. Acrylamide is produced during the roasting of coffee beans, but the roasting process is an ...essential step in determining the taste of coffee. Acrylamide content in coffee has been suggested to decrease by reacting with proteins and/or other substances during storage, but details are unknown. Investigation of acrylamide adducts may contribute to a strategy for acrylamide reduction in coffee. In this study, a stable isotope labeling technique, combined with high-resolution mass spectrometry, allows the identification of acrylamide adducts (3-hydroxypyridine-acrylamide and pyridine-acrylamide) in canned milk coffee. Other acrylamide adducts derived from milk coffee proteins, Lys-acrylic acid and CysSO2-acrylic acid, were identified. During a 4-month storage period, the formation of these four adducts was found to reduce the total content of acrylamide by 75.3% in canned milk coffee. Therefore, endogenous proteins can be used in acrylamide reduction.
Ethoxidol as a Broad-spectrum Adaptogen Irina, Zhigacheva V; Natalya, Krikunova I; Vladimir, Binyukov I ...
Current molecular pharmacology,
01/2023, Letnik:
16, Številka:
1
Journal Article
Recenzirano
Stress factors lead to a shift in the antioxidant-prooxidant relationship, allowing an increase in the generation of reactive oxygen species (ROS) by mitochondria, which results in the development of ...oxidative stress. Consequently, it is possible to put forward an assumption that drugs which reduce the excessive generation of ROS by these organelles should increase the body's resistance to stress factors. Antioxidants can be used as such drugs. In this regard, the aim of this work was to study the bioenergetics characteristic of mitochondria under stress conditions and under the action of 2-ethyl-6-methyl-3-hydroxypyridinium hydroxybutanedioate (ethoxidol).
The antiradical activity of the drug was evaluated by the chemiluminescent method (CL). The functional state of the mitochondria was studied with reference to the level of lipid peroxidation by the spectrofluorimetry and in terms of fatty acid composition of mitochondrial membranes using the chromatography technique. The study of mitochondrial morphology was performed employing the method of atomic force microscopy.
The injection in mice of ethoxidol at a dose of 10
mol/kg for 7 days led to the prevention of the stress-induced increase in the intensity of LPO in the membranes of the mitochondria, and swelling of these organelles; it also prevented a decrease in the content of unsaturated fatty acids, containing 18 and 20 carbon atoms. At the same time, ethoxidol increased the life expectancy of mice by 3.0-4.2 times in conditions of various types of hypoxia.
The adaptogenic properties of ethoxidol can be attributed to its antiradical and antioxidant properties.
The review is devoted to a comparative analysis of the clinical efficacy of the original domestic derivatives of 3-hydroxypyridine and succinic acid (emoxipine, reamberin and mexidol) in comparison ...with the results of an experimental study of their dopaminergic action. The position that the dopaminomimetic activity of emoxipin, reamberin and mexidol largely determines their anti-ischemic, antihypoxic, insulin-potentiating neuroprotective, nootropic and antidepressant potential has been substantiated. A comparative analysis of the safety profile of emoxipine, reamberin and mexidol was carried out, taking into account potential and real side-effects caused by iatrogenic deviations from the eudopaminergic state. It has been shown that mexidol (2-ethyl-6-methyl-3-hydroxypyridine succinate), which is simultaneously a derivative of 3-hydroxypyridine and succinic acid, has the best balance of efficacy and safety. A generalized assessment of the available data on the successful use of off-label derivatives of 3-hydroxypyridine and succinic acid indicates the advisability of a significant expansion of indications for their clinical use. The authors resume that the «therapeutic retargeting» of emoxipin, reamberin and mexidol (i.e. their use for qualitatively new indications) will contribute to progress in the treatment of socially significant and most common diseases.
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•Pyrocatechol yielded CSs with smaller surface area and size than did resorcinol.•CSs activation augmented their pore texture but had little effect on their size.•Activation of CSs by ...O2 adsorption-desorption cycles yielded wider micropores.•Physically-activated CSs showed the highest capacitance at 1Ag−1, 17.3μFcm−2.•Areal capacitance was higher in N-doped CSs (ca. 1.5 at.% N) than in non-doped CSs.
In this study, polymer spheres (PSs) were prepared by an emulsion polymerization of resorcinol, pyrocatechol, or 3-hydroxypyridine with formaldehyde under basic conditions. Carbon spheres (CSs) were obtained by carbonization of PSs at 900°C, and some of them were activated with KOH and oxygen adsorption-desorption cycles. Resorcinol and pyrocatechol differ in their reactivity during the polycondensation reaction with formaldehyde. The use of 3-hydroxypyridine allowed the introduction of N functionalities in the final CSs obtained. The objective was to examine the effects on the diameter of the carbon spheres, their surface physics and chemistry, and their performance as electrochemical double-layer (EDL) capacitors produced by: i) the replacement of resorcinol with pyrocatechol in the polymerization reaction and the utilization of different carbon sphere activation methods; and ii) the introduction of N functionalities. The size, surface area, micropore volume, total pore volume, and micropore width of the CSs ranged between 159 and 856nm, 7 and 1156m2g−1, 0.06 and 0.46cm3g−1, 0.15 and 0.58cm3g−1, and 0.50 and 1.23nm, respectively. The physically-activated sample showed the highest capacitance at 1Ag−1, 200Fg−1 or 17.3μFcm−2. Capacitance was higher in N-doped samples than in the non-doped sample.
We report an efficient method to prepare polysubstituted 3-hydroxypyridines from amino acids, propargyl alcohols, and arylboronic acids. The process involves Pd(0)-catalyzed anti-selective arylative ...cyclizations of N-propargyl-N-tosyl-aminoaldehydes with arylboronic acids (“anti-Wacker”-type cyclization), oxidation of the resulting 5-substituted-3-hydroxy-1,2,3,6-tetrahydropyridines to 3-oxo derivatives, and elimination of p-toluenesulfinic acid. This method provides diverse polysubstituted 3-hydroxypyridines, whose hydroxy group can be further substituted by a cross-coupling reaction via a triflate.
