Day: December 9, 2022

Liu, Chun published the artcileA fast and oxygen-promoted protocol for the ligand-free Suzuki reaction of 2-halogenated pyridines in aqueous media, Category: pyridine-derivatives, the publication is Chemical Communications (Cambridge, United Kingdom) (2009), 6267-6269, database is CAplus and MEDLINE.

A fast protocol has been developed for the construction of 2-aryl-substituted pyridine derivatives by the oxygen-promoted, ligand-free, Pd(OAc)₂-catalyzed Suzuki reaction of 2-halogenated pyridines in aqueous isopropanol.

Chemical Communications (Cambridge, United Kingdom) published new progress about 85237-71-4. 85237-71-4 belongs to pyridine-derivatives, auxiliary class Pyridine,Benzene, name is 5-Methyl-2-(p-tolyl)pyridine, and the molecular formula is C13H13N, Category: pyridine-derivatives.

Referemce:
https://en.wikipedia.org/wiki/Pyridine,
Pyridine | C5H5N – PubChem

Jin, Lei published the artcileElectrochemistry and coordination behaviors of hypoxanthine-Au (III) ion in the cyanide-free gold electrodeposition, Safety of Pyridine-3-sulfonic acid, the publication is Journal of the Electrochemical Society (2020), 167(2), 022511, database is CAplus.

Alkaloid hypoxanthine is a novel complexant for green cyanide-free Au(III) electrodeposition. The electrochem. and coordination behaviors of hypoxanthine-Au(III) ion in the green cyanide-free bath were studied. The electrochem. behavior confirms that hypoxanthine-Au(III) ion is in the irreversible two-step electro-reductions with the 1st controlled by diffusion and the 2nd by diffusion and electrochem. The stability constant of hypoxanthine-Au(III) ion is 4.8 × 10³⁰. DFT calculations further indicate that the optimal coordination structure is N3-Au-N7 with the N-Au average bond energy of 11.03 eV. The bath component of K citrate plays almost no influence, whereas the additive of sulfocompounds shows a significant effect on the electro-reduction of hypoxanthine-Au(III) ion. Based on the cyanide-free Au(III) electrodeposition bath, the obtained Au coating is fine and compact in grains without organic inclusion and in the resistivity of 2.84 × 10^-8 Ω m.

Journal of the Electrochemical Society published new progress about 636-73-7. 636-73-7 belongs to pyridine-derivatives, auxiliary class Pyridine,Sulfonic acid, name is Pyridine-3-sulfonic acid, and the molecular formula is C5H5NO3S, Safety of Pyridine-3-sulfonic acid.

Referemce:
https://en.wikipedia.org/wiki/Pyridine,
Pyridine | C5H5N – PubChem

Zhang, Qian published the artcileDDQ: the chlorinating reagent and oxidant for the ligand-directed ortho-chlorination of 2-arylpyridines, Quality Control of 85237-71-4, the publication is Organic Chemistry Frontiers (2014), 1(6), 694-697, database is CAplus.

A new and simple protocol for palladium-catalyzed ligand-directed ortho-chlorination of 2-arylpyridines with DDQ was developed, generating the chlorinated products in good to excellent yields. DDQ played dual role as both the chlorinating reagent and oxidant in this reaction. Moreover, high regioselectivity was observed for 2-arylpyridines bearing a meta-substituent in the aryl ring moiety, and chlorination could take place at the less sterically hindered ortho-C-H bond.

Organic Chemistry Frontiers published new progress about 85237-71-4. 85237-71-4 belongs to pyridine-derivatives, auxiliary class Pyridine,Benzene, name is 5-Methyl-2-(p-tolyl)pyridine, and the molecular formula is C3H6BrNaO3S, Quality Control of 85237-71-4.

Referemce:
https://en.wikipedia.org/wiki/Pyridine,
Pyridine | C5H5N – PubChem

Zhang, Xiaofei published the artcileAlkylations of Arylboronic Acids including Difluoroethylation/Trifluoroethylation via Nickel-Catalyzed Suzuki Cross-Coupling Reaction, Recommanded Product: (6-Ethoxypyridin-3-yl)boronic acid, the publication is Advanced Synthesis & Catalysis (2015), 357(12), 2721-2727, database is CAplus.

An efficient alkylation method of functionalized alkyl halides under mild nickel-catalyzed C(sp³) – C(sp²) Suzuki cross-coupling conditions was described. The features of this approach are excellent functional group compatibility, low cost nickel catalyst, and the use of a mild base. This is also the first successful example of the nickel-catalyzed direct 2,2-difluoroethylation or 2,2,2-trifluoroethylation of aryl-/heteroarylboronic acids.

Advanced Synthesis & Catalysis published new progress about 612845-44-0. 612845-44-0 belongs to pyridine-derivatives, auxiliary class Pyridine,Boronic acid and ester,Ether,Boronic Acids,Boronic acid and ester, name is (6-Ethoxypyridin-3-yl)boronic acid, and the molecular formula is C19H17N2NaO4S, Recommanded Product: (6-Ethoxypyridin-3-yl)boronic acid.

Referemce:
https://en.wikipedia.org/wiki/Pyridine,
Pyridine | C5H5N – PubChem

Liu, Juanjuan published the artcileIodine-promoted synthesis of acylindolizine derivatives from acetylenecarboxylates and pyridinium, isoquinolinium, or quinolinium ylides, Category: pyridine-derivatives, the publication is Monatshefte fuer Chemie (2014), 145(4), 617-625, database is CAplus.

An iodine-promoted synthesis of acylindolizinecarboxylates via 1,3-dipolar cycloaddition of nitrogen ylides with acetylenecarboxylates and subsequent aromatization for the generation of a wide range of structurally interesting, pharmacol. and photoelec. significant compounds is reported. Only readily available materials, mild conditions, and operationally trivial reaction protocols were required.

Monatshefte fuer Chemie published new progress about 17281-59-3. 17281-59-3 belongs to pyridine-derivatives, auxiliary class Pyridine,Nitrile,Salt, name is 1-(Cyanomethyl)pyridin-1-ium chloride, and the molecular formula is C7H7ClN2, Category: pyridine-derivatives.

Referemce:
https://en.wikipedia.org/wiki/Pyridine,
Pyridine | C5H5N – PubChem

Duan, Jingli published the artcileBioequivalence of domestic and imported betahistine mesylate tablets in healthy volunteers, Product Details of C10H20N2O6S2, the publication is Zhongguo Linchuang Yaolixue Zazhi (2003), 19(1), 42-45, database is CAplus.

The objective of this study was to determine the bioequivalence of domestic and imported betahistine mesylate in 20 healthy volunteers. A single dose of 24 mg domestic and imported betahistine mesylate tablets was given according to an open randomized 2-way crossover design. Plasma concentration of the main metabolite of betahistine, pyridine-2-ethanoic acid, was determined by HPLC/MS/MS method. The pharmacokinetics parameters of the two products were as follow: C_max 308.6 ± 208.8 mg L^-1 and 339.4 ± 213.4 mg L^-1; t_max 1.13 ± 0.66 h and 0.98 ± 0.47 h; AUC_0-t 1168.5 ± 794.9 mg L^-1 and 1129.3 ± 725.2 mg L^-1; AUC_0-∞ were 1213.2 ± 819.2 mg L^-1 and 1178.9 ± 752.5 mg L^-1, resp. The relative bioavailability of domestic product was (106.3 ± 29.1%). The results demonstrated that the two formations were bioequivalent by anal. of variance, two-one side test and 90% internal confidence.

Zhongguo Linchuang Yaolixue Zazhi published new progress about 54856-23-4. 54856-23-4 belongs to pyridine-derivatives, auxiliary class Pyridine,Salt,Amine,Inhibitor,Inhibitor, name is N-Methyl-2-(pyridin-2-yl)ethan-1-amine dimethanesulfonate, and the molecular formula is C10H20N2O6S2, Product Details of C10H20N2O6S2.

Referemce:
https://en.wikipedia.org/wiki/Pyridine,
Pyridine | C5H5N – PubChem

Motomura, Naoki published the artcileVisualization of calcium channel blockers in human adrenal tissues and their possible effects on steroidogenesis in the patients with primary aldosteronism (PA), Recommanded Product: Dimethyl 2,6-dimethyl-4-(2-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylate, the publication is Journal of Steroid Biochemistry and Molecular Biology (2022), 106062, database is CAplus and MEDLINE.

Voltage-gated L-type calcium channel (CaV) isoforms are well known to play pivotal tissue-specific roles not only in vasoconstriction but also in adrenocortical steroidogenesis including aldosterone biosynthesis. Alpha-1C subunit calcium channel (CC) (CaV1.2) is the specific target of anti-hypertensive CC blockers (CCBs) and its Alpha-1D subunit (CaV1.3) regulates depolarization of cell membrane in aldosterone-producing cells. Direct effects of CCBs on aldosterone biosynthesis were previously postulated but their intra-adrenal distribution and effects on steroid production in primary aldosteronism (PA) patients have remained virtually unknown. In this study, frozen tissue specimens constituting tumor, adjacent adrenal gland and peri-adrenal adipose tissues of nine aldosterone-producing adenoma (APA) cases were examined for visualization of amlodipine and aldosterone themselves using matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI). Liquid chromatog.-mass spectrometry (LC-MS) anal. was also performed to quantify amlodipine and 17 adrenal steroids in those cases above and compared the findings with immunohistochem. anal. of steroidogenic enzymes and calcium channels (CaV1.2 and CaV1.3). Effects of amlodipine on mRNA level of aldosterone biosynthetic enzymes were also explored using human adrenocortical carcinoma cell line (H295R). Amlodipine-specific peak (m/z 407.1 > 318.1) was detected only in amlodipine treated cases. Accumulation of amlodipine was marked in adrenal cortex compared to peri-adrenal adipose tissues but not significantly different between APA tumors and adjacent adrenal glands, which was subsequently confirmed by LC-MS quantification. Intra-adrenal distribution of amlodipine was generally consistent with that of CCs. In addition, quant. steroid profiles using LC-MS and in vitro study demonstrated the lower HSD3B activities in amlodipine treated cases. Immunoreactivity of CaV1.2 and HSD3B2 were also correlated. We report the first demonstration of specific visualization of amlodipine in human adrenal tissues by MALDI-MSI. Marked amlodipine accumulation in the adrenal glands suggested its direct effects on steroidogenesis in PA patients, possibly targeting on CaV1.2 and suppressing HSD3B activity.

Journal of Steroid Biochemistry and Molecular Biology published new progress about 21829-25-4. 21829-25-4 belongs to pyridine-derivatives, auxiliary class Membrane Transporter/Ion Channel,Calcium Channel, name is Dimethyl 2,6-dimethyl-4-(2-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylate, and the molecular formula is C17H18N2O6, Recommanded Product: Dimethyl 2,6-dimethyl-4-(2-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylate.

Referemce:
https://en.wikipedia.org/wiki/Pyridine,
Pyridine | C5H5N – PubChem

Kawasaki-Takasuka, Tomoko published the artcileThe modified trifluoromethylation protocol applicable to electronically deficient iodopyridinones, Computed Properties of 197958-29-5, the publication is Tetrahedron (2015), 71(38), 6824-6831, database is CAplus.

Utilization of a mixed solvent system of DMF/HMPA = 1/1 (volume/volume) to the KF/CuI/TMSCF₃ reagent system proved to significantly affect the reaction, realizing convenient introduction of a trifluoromethyl (CF₃) group not only to electron-deficient iodopyridinones, e.g., I, with quite a few previous successful examples but also to aliphatic vinylic iodides such as 2-iodocyclohex-2-en-1-one, 1-iodocyclohex-1-ene, (E)- and (Z)-(4-iodobut-3-en-1-yl)benzene.

Tetrahedron published new progress about 197958-29-5. 197958-29-5 belongs to pyridine-derivatives, auxiliary class Pyridine,Boronic acid and ester, name is 2-Pyridinylboronic acid, and the molecular formula is C5H6BNO2, Computed Properties of 197958-29-5.

Referemce:
https://en.wikipedia.org/wiki/Pyridine,
Pyridine | C5H5N – PubChem

Tanaka, Ryo published the artcileCatalytic Hydrogenation of Carbon Dioxide Using Ir(III)-Pincer Complexes, Recommanded Product: 2,6-Bis((di-tert-butylphosphino)methyl)pyridine, the publication is Journal of the American Chemical Society (2009), 131(40), 14168-14169, database is CAplus and MEDLINE.

Catalytic hydrogenation of carbon dioxide in aqueous potassium hydroxide was performed using a newly synthesized isopropyl-substituted PNP-pincer iridium trihydride complex as catalyst. Potassium formate was obtained with turnover number up to 3,500,000 and turnover frequency of 150,000 h^-1.

Journal of the American Chemical Society published new progress about 338800-13-8. 338800-13-8 belongs to pyridine-derivatives, auxiliary class Bis-phosphine Ligands, name is 2,6-Bis((di-tert-butylphosphino)methyl)pyridine, and the molecular formula is C7H13BrSi, Recommanded Product: 2,6-Bis((di-tert-butylphosphino)methyl)pyridine.

Referemce:
https://en.wikipedia.org/wiki/Pyridine,
Pyridine | C5H5N – PubChem

Fujinaga, Masayuki published the artcileSynthesis and evaluation of 6-[1-(2-[¹⁸F]fluoro-3-pyridyl)-5-methyl-1H-1,2,3-triazol-4-yl]quinoline for positron emission tomography imaging of the metabotropic glutamate receptor type 1 in brain, Category: pyridine-derivatives, the publication is Bioorganic & Medicinal Chemistry (2011), 19(1), 102-110, database is CAplus and MEDLINE.

The purpose of this study was to synthesize 6-[1-(2-[¹⁸F]fluoro-3-pyridyl)-5-methyl-1H-1,2,3-triazol-4-yl]quinoline ([¹⁸F]FPTQ, [¹⁸F]7a) and to evaluate its potential as a positron emission tomog. ligand for imaging metabotropic glutamate receptor type 1 (mGluR1) in the rat brain. Compound [¹⁸F]7a was synthesized by [¹⁸F]fluorination of 6-[1-(2-bromo-3-pyridyl)-5-methyl-1H-1,2,3-triazol-4-yl]quinoline (7b) with potassium [¹⁸F]fluoride. At the end of synthesis, 1280-1830 MBq (n = 8) of [¹⁸F]7a was obtained with >98% radiochem. purity and 118-237 GBq/μmol specific activity using 3300-4000 MBq of [¹⁸F]F^–. In vitro autoradiog. showed that [¹⁸F]7a had high specific binding with mGluR1 in the rat brain. Biodistribution study using a dissection method and small-animal PET showed that [¹⁸F]7a had high uptake in the rat brain. The uptake of radioactivity in the cerebellum was reduced by unlabeled 7a and mGluR1-selective ligand JNJ-16259685 (2), indicating that [¹⁸F]7a had in vivo specific binding with mGluR1. Because of a low amount of radiolabeled metabolite present in the brain, [¹⁸F]7a may have a limiting potential for the in vivo imaging of mGluR1 by PET.

Bioorganic & Medicinal Chemistry published new progress about 39856-58-1. 39856-58-1 belongs to pyridine-derivatives, auxiliary class Pyridine,Bromide,Amine, name is 2-Bromopyridin-3-amine, and the molecular formula is C5H5BrN2, Category: pyridine-derivatives.

Referemce:
https://en.wikipedia.org/wiki/Pyridine,
Pyridine | C5H5N – PubChem