Category: pyridine-derivatives

Reisenbauer, Julia C. published the artcileDevelopment of an Operationally Simple, Scalable, and HCN-Free Transfer Hydrocyanation Protocol Using an Air-Stable Nickel Precatalyst, Computed Properties of 91-02-1, the publication is Organic Process Research & Development (2022), 26(4), 1165-1173, database is CAplus.

Herein, HCN-free transfer hydrocyanation of alkenes and alkynes that employed com. available aliphatic nitriles R¹CC(CN)R¹ [R¹ = Ph, 2-MeC₆H₄, 4-PhC₆H₄, etc.; R² = H; R¹R² = (CH₂)₆] and alkenyl nitriles R¹C=C(CN)R¹ [R¹ = nPr, nBu, SiMe₃ R² = nPr, nBu, Ph] as sacrificial HCN donors in combination with a catalytic amount of air-stable and inexpensive NiCl₂ as a precatalyst and a cocatalytic Lewis acid was reported. The scalability and robustness of the catalytic process were demonstrated by the hydrocyanation of α-methylstyrene on a 100 mmol scale (11.4 g of product obtained) using 1 mol % of the Ni catalyst. In addition, the feasibility of the dehydrocyanation protocol using the air-stable Ni(II) precatalyst and norbornadiene as a sacrificial acceptor was showcased by the selective conversion of an aliphatic nitrile into the corresponding alkene.

Organic Process Research & Development published new progress about 91-02-1. 91-02-1 belongs to pyridine-derivatives, auxiliary class Pyridine,Benzene,Ketone, name is Phenyl(pyridin-2-yl)methanone, and the molecular formula is C12H9NO, Computed Properties of 91-02-1.

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

Shaffer, David W. published the artcileSpin-state diversity in a series of Co(II) PNP pincer bromide complexes, Quality Control of 338800-13-8, the publication is Dalton Transactions (2016), 45(44), 17910-17917, database is CAplus and MEDLINE.

The authors describe the structural and electronic impacts of modifying the bridging atom in a family of Co(II) pincer complexes Co(t-Bu)₂P^EPy^EP(t-Bu)₂Br₂ (Py = pyridine, E = CH₂, NH, and O for compounds 1–3, resp.). Structural characterization by single crystal x-ray diffraction indicates that compounds 1 and 3 are 5-coordinate complexes with both bromides bound to the Co ion, while compound 2 is square planar with one bromide in the outer coordination sphere. The reduction potentials of 1–3, characterized by cyclic voltammetry, are consistent with the increasing electron-withdrawing character of the pincer ligand as the linker (E) between the pyridine and phosphine arms becomes more electroneg. Magnetic property studies of compounds 1 and 2 confirm high- and low-spin behavior, resp., through a broad temperature range. However, complex 3 features an unusual combination of high spin S = 3/2 Co(II) and temperature dependent spin-crossover between S = 3/2 and S = 1/2 states. The different magnetic behaviors observed among the three CoBr₂ pincer complexes reflects the importance of small ligand perturbations on overall coordination geometry and resulting spin state properties.

Dalton Transactions 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 C7H5ClN2S, Quality Control of 338800-13-8.

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

Gawri, Rahul published the artcileThe anabolic effect of inorganic polyphosphate on chondrocytes is mediated by calcium signalling, Synthetic Route of 21829-25-4, the publication is Journal of Orthopaedic Research (2022), 40(2), 310-322, database is CAplus and MEDLINE.

Inorganic polyphosphates (polyP) are polymers composed of phosphate residues linked by energy-rich phosphoanhydride bonds. As polyP can bind calcium, the hypothesis of this study is that polyP enters chondrocytes and exerts its anabolic effect by calcium influx through calcium channels. PolyP treatment of cartilage tissue formed in 3D culture by bovine chondrocytes showed an increase in proteoglycan accumulation but only when calcium was also present at a concentration of 1.5 mM. This anabolic effect could be prevented by treatment with either ethylene glycol-bis(β-aminoethyl ether)-N,N,N,N-tetraacetic acid or the calcium channel inhibitors gadolinium and nifedipine. Calcium and polyP cotreatment of chondrocytes in monolayer culture resulted in calcium oscillations that were polyP chain length specific and were inhibited by gadolinium and nifedipine. The calcium influx resulted in increased gene expression of sox9, collagen type II, and aggrecan which was prevented by treatment with either calphostin, an inhibitor of protein kinase C, and W7, an inhibitor of calmodulin; suggesting activation of the protein kinase C-calmodulin pathway. Tracing studies using 4,6-diamidino-2-phenylindole, Mitotracker Red, and/or Fura-AM staining showed that polyP was detected in the nucleus, mitochondria, and intracellular vacuoles suggesting that polyP may also enter the cell. PolyP colocalizes with calcium in mitochondria. This study demonstrates that polyP requires the influx of calcium to regulate chondrocyte matrix production, likely via activating calcium signaling. These findings identify the mechanism regulating the anabolic effect of polyP in chondrocytes which will help in its clin. translation into a therapeutic agent for cartilage repair.

Journal of Orthopaedic Research 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, Synthetic Route of 21829-25-4.

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

Hertog, Adriaan Den published the artcileThe action of some new aminopyridines on mammalian nonmyelinated nerve fibers, Application In Synthesis of 18437-58-6, the publication is European Journal of Pharmacology (1987), 142(1), 115-20, database is CAplus.

The effects of a recently synthesized series of aminopyridines (APs) 2-methyl-4-AP, 2-chloro-4-AP, and 2-(N,N-methylbenzyl)amino-4-AP (2A-7) on voltage-operated Na⁺ and K⁺ channels and on the Na⁺ pump activity of nonmyelinated fibers of the guinea-pig vagus nerve were studied with the sucrose-gap method. The compound action potential evoked by elec. stimulation and the propagation velocity along the nerve were not affected by 2-methyl-4-AP or 2-chloro-4-AP up to a concentration of 10^-3 M. The post-tetanic potential (PTH) evoked by repetitive stimulation of the nerve and reflecting Na⁺ pumping was also not affected by these agents. The amplitude and duration of the compound action potential were enhanced to some extent by 2-methyl-4-AP at the highest concentration used (3 × 10^-3 M); this action was also observed and was more pronounced with 4-aminopyridine (4-AP). The other aminopyridine 2A-7 (3 × 10^-5-3 × 10^-4 M) caused suppression of the compound action potential, a diminished propagation velocity and a reduction of the PTH, an action also observed with lidocaine. These results show that 2-methyl-4-AP and 3-chloro-4-AP did not affect the voltage-operated Na⁺ or K⁺ channels in nonmyelinated fibers of the vagus nerve. Only 2-methyl-4-AP had a small 4-AP-like action at high concentrations The aminopyridine 2A-7 possesses a local anesthetic action as reflected by the inhibition of voltage-operated Na⁺ channels.

European Journal of Pharmacology published new progress about 18437-58-6. 18437-58-6 belongs to pyridine-derivatives, auxiliary class Pyridine,Amine, name is 4-Amino-2-picoline, and the molecular formula is C6H8N2, Application In Synthesis of 18437-58-6.

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

Romito, Deborah published the artcileNon-covalent bridging of bithiophenes through chalcogen bonding grips, Category: pyridine-derivatives, the publication is New Journal of Chemistry (2020), 44(17), 6732-6738, database is CAplus.

In this work, chalcogen functionalized dithiophenes, equipped on both extremities with chalcogen-bonding recognition heterocycles, have been prepared following two synthetic pathways. The insertion of the chalcogenazolo[5,4-β]pyridine allows the control of the organization at the solid state. X-Ray diffraction anal. of the single crystals, showed that the Te-doped derivatives give the most persistant assemblies, with the mols. arranging at solid-state in wire-like polymeric structures through Te···N interactions. As expected, the introduction of the Se and Te atoms, dramatically decreases the emission properties, with the Te-bearing congeners being virtually non emissive.

New Journal of 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

Barraclough, Paul published the artcileInotropic ‘A’ ring substituted sulmazole and isomazole analogs, Category: pyridine-derivatives, the publication is Journal of Medicinal Chemistry (1990), 33(8), 2231-9, database is CAplus and MEDLINE.

A series of “A” ring substituted sulmazole I [R = 4-, 5-, 6-MeO, 5-NO₂, 5-Cl, 5-Me, 5-Ac; X = S, S(O), O] and isomazole analogs II [R = 2-, 5-, 6-MeO, 5-NH₂, 5-NO₂; X = S, S(O), O] were prepared and evaluated as inotropic agents. Thus, 5-methoxy-2,3-pyridinediamine was cyclized with 2-methoxy-4-(methylthio)benzoic acid to give I (R = 5-MeO, X = S), which was oxidized to give I [R = 5-MeO, X = S(O)]. PK_A‘s, protonation sites, and log P values were measured for selected compounds and their electronic properties were calculated No simple correlation between inotropic activity and pK_A, protonation site, or log P value was observed However, in vitro inotropism did correlate with the calculated charge d. of the “B” ring imidazo nitrogen atom. The 6-position of sulmazole appeared to be the most tolerant toward substituents, the 6-amino derivative I [R = 6-NH, X = S(O)] being a more potent inotrope than sulmazole itself. 4-Methoxyisomazole had comparable in vivo inotropic properties to those of isomazole.

Journal of Medicinal Chemistry published new progress about 33631-04-8. 33631-04-8 belongs to pyridine-derivatives, auxiliary class Pyridine,Amine,Ether, name is 2-Methoxypyridine-3,4-diamine, and the molecular formula is C6H9N3O, Category: pyridine-derivatives.

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

McConnell, Danielle L. published the artcileSynthesis of Bench-Stable N-Quaternized Ketene N,O-Acetals and Preliminary Evaluation as Reagents in Organic Synthesis, Recommanded Product: Phenyl(pyridin-2-yl)methanone, the publication is Journal of Organic Chemistry (2021), 86(18), 13025-13040, database is CAplus and MEDLINE.

In this report, a general synthetic approach to a variety of bench-stable N-quaternized ketene N,O-acetals I (R = H, 2-Ph, 4-Me, 2,6-Cl₂, etc.; X = OTf, NTf₂) via treatment of pyridine II or aniline bases with acetylenic ethers R¹CC (R¹ = OEt, 4-methoxyphenyl) and an appropriate Bronsted or Lewis acid (triflic acid, triflimide, or scandium(III) triflate) have been described. The resulting pyridinium I and anilinium salts C₆H₅N⁺((CH₃)CH₂)C(=CH₂)R¹ X^– can be used as reagents or synthetic intermediates in multiple reaction types. For example, N-(1-ethoxyvinyl)pyridinium or anilinium salts can thermally release highly reactive O-Et ketenium ions for use in acid catalyst-free electrophilic aromatic substitutions. N-(1-ethoxyvinyl)-2-halopyridinium salts I (R = 2-Cl, 2-Br) can be employed in peptide couplings as a derivative of Mukaiyama reagent (2-chloro-1-methylpyridinium iodide) or react with phenylmethanamine in nucleophilic aromatic substitutions under mild conditions. These preliminary reactions illustrate the broad potential of these currently understudied compounds in organic synthesis.

Journal of Organic Chemistry published new progress about 91-02-1. 91-02-1 belongs to pyridine-derivatives, auxiliary class Pyridine,Benzene,Ketone, name is Phenyl(pyridin-2-yl)methanone, and the molecular formula is C12H9NO, Recommanded Product: Phenyl(pyridin-2-yl)methanone.

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

Sutherland, Hamish S. published the artcileSynthesis and Structure-activity Relationships of Antitubercular 2-Nitroimidazooxazines Bearing Heterocyclic Side Chains, HPLC of Formula: 870459-90-8, the publication is Journal of Medicinal Chemistry (2010), 53(2), 855-866, database is CAplus and MEDLINE.

Previously, biphenyl analogs of the antituberculosis drug PA-824 were found to display improved potencies against M. tuberculosis but were poorly soluble Heterobiaryl analogs of these, e.g., I (X = 2,5-thiophenediyl, R = 4-F), in which the first Ph ring was replaced with various 5-membered ring heterocycles, were prepared with the aim of identifying potent new candidates with improved aqueous solubility The compounds were constructed by coupling the chiral 2-nitroimidazooxazine II with various halomethyl-substituted arylheterocycles, by cycloadditions to a propargyl ether derivative of this alc., or by Suzuki couplings on haloheterocyclic Me ether derivatives The arylheterocyclic compounds were all more hydrophilic than their corresponding biphenyl analogs, and several showed solubility improvements. 1-Methylpyrazole, e.g., I (X = 1-methyl-3,5-pyrazolediyl, R = 4-F₃C), 1,3-linked-pyrazole, e.g., I (X = 1,3-pyrazolediyl, R = 4-F), 2,4-linked-triazole, e.g., I [X = 1,2,3-triazole-2,4-diyl, R = 4-(CF₃O)] and tetrazole analogs, e.g., I (X = 2,5-tetrazolediyl, R = H) had 3- to 7-fold higher MIC potencies against replicating M. tuberculosis than predicted by their lipophilicities. Two pyrazole analogs were >10-fold more efficacious than the parent drug in a mouse model of acute M. tuberculosis infection, and one displayed a 2-fold higher solubility

Journal of Medicinal Chemistry published new progress about 870459-90-8. 870459-90-8 belongs to pyridine-derivatives, auxiliary class Trifluoromethyl,Pyridine,Fluoride,Boronic acid and ester,Boronic Acids,Boronic acid and ester, name is (4-(Trifluoromethyl)pyridin-2-yl)boronic acid, and the molecular formula is C4HN5, HPLC of Formula: 870459-90-8.

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

Karaman, Rafik published the artcileSymmetrical and unsymmetrical quadruply aza-bridged, closely interspaced, cofacial bis(5,10,15,20-tetraphenylporphyrin)s. 2. Synthesis, characterization, and conformational effects of solvents, Formula: C5H5NO3S, the publication is Journal of the American Chemical Society (1992), 114(12), 4889-98, database is CAplus.

Title compounds I [X = NR, R = 3-pyridylsulfonyl (R¹), 1-methylpyridinium-3-sulfonyl (R²), CONH₂, cyano, tosyl; X = OCO₂, R = R¹, cyano] have been synthesized and fully characterized by 2-dimensional ¹H-¹H NMR (COSY), 2-dimensional ¹³C-¹H NMR, fast-atom-bombardment mass spectrometry, UV/vis, IR, and fluorescence spectral techniques. It was established, on the basis of ¹H NMR, UV/vis, and emission spectrophotometries, that I (X = NR, R = R¹, R², tosyl) exist in more than one conformational in DMSO and in only one sym. conformation in CHCl₃. Their biszinc complexes and tetraprotonated derivatives exist in one conformation regardless of the solvent. These observations have been attributed to an interaction between DMSO and the pyrrolic N-H protons of the porphyrin cores which is inhibited by metalation or protonation. Mol. dynamics calculations reveal that the intracavity interactions of I (X = NR, R = R¹) with DMSO are more important than the intercavity interactions which result in discrete, unsym. conformations of the dimer. In contrast, I (X = OCO₂, R = R¹, cyano; X = NR, R = cyano, CONH₂) do not show any conformational changes upon switching from CHCl₃ to DMSO. This is attributed to the long interplanar distances calculated for the porphyrin dimers which prevent intracavity coordination of DMSO with both porphyrin moieties. ¹H NMR variable-temperature experiments of I (X = NR, R = R¹) in DMSO show that the conformation of the dimer is greatly affected by temperature While at room temperature I (X = NR, R = R¹) exists in more than one conformation, at higher temperatures (150°) only one conformation is populated. It is proposed that at room temperature, the existence of a H-bonding network between DMSO and the dimer results in more than one conformation, while at higher temperatures the network is destroyed to furnish an average conformation.

Journal of the American Chemical 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, Formula: C5H5NO3S.

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

Gimenez Plaza, J. published the artcile2-Pyridinecarboxaldehyde 2-pyridylhydrazone as analytical reagent. III. Spectrophotometric determination of cobalt(II), Recommanded Product: 2-((2-(Pyridin-2-yl)hydrazono)methyl)pyridine, the publication is Afinidad (1980), 37(367), 243-6, database is CAplus.

A method for the spectrophotometric determination of Co(II) is based on the formation of a 1:1 complex of Co(II) with 2-pyridinecarboxaldehyde 2-pyridylhydrazone (I). Approx. 10 mL EtOH was added to the sample with 3 mL HOAc/NaOAc buffer (pH 6) and 5 mL 0.002M I and the total volume was adjusted to 25 mL. The absorbance was measured at 350-90 nm after 15 min. The relative error was 0.3-0.5% for determining 2-5 ppm Co. Significant interference was observed from � ppm Hg(II), Cu(II), Sn(II), Fe(III), Ni(II), Zn(II), Fe(II), Pd(II), Au(III), Mo(VI), V(V), Os(VIII), and Ce(IV). The logarithm of the stability constant of the Cr-I complex is 6.88.

Afinidad published new progress about 2215-33-0. 2215-33-0 belongs to pyridine-derivatives, auxiliary class Pyridine,Amine, name is 2-((2-(Pyridin-2-yl)hydrazono)methyl)pyridine, and the molecular formula is C11H10N4, Recommanded Product: 2-((2-(Pyridin-2-yl)hydrazono)methyl)pyridine.

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