Month: December 2022

Lombardini, John B. published the artcileQuantitative analysis of the combination dose-effects of taurine and taurine analogs on the phosphorylation of an ∼44-Kd protein present in a mitochondrial subfraction of rat heart, COA of Formula: C5H5NO3S, the publication is Journal of Cardiovascular Pharmacology (1996), 28(1), 107-114, database is CAplus and MEDLINE.

Combinations of taurine and analogs of taurine that partially contain the N-C-C-S moiety within a semirigid saturated ring structure were tested for their effects on the phosphorylation of an ∼44-Kd protein present in the mitochondrial fraction of rat heart. (±)-Piperidine-3-sulfonic acid (PiP), an inhibitor of the phosphorylation of the ∼44-Kd protein with activity approx. similar to that of taurine, was observed to be mutually exclusive with taurine, i.e., to have a similar mode of action. The combination of taurine plus PiP in a fixed ratio mixture of 1:1 was slightly antagonistic at all concentrations (±)-Aminotetrahydrothiopyran-1,1-dioxide (APS), a sulfone derivative of taurine with a net pos. charge, also has approx. the same inhibitory activity as taurine. However, APS was mutually nonexclusive with taurine when tested in combination and thus appears to act independently of taurine. Taurine plus APS in a fixed ratio mixture of 3:1 was highly antagonistic at low concentrations of the mixture, approached an additive relation at 50% saturation, and became synergistic at high concentrations of the mixture Three analogs of taurine, pyridine-3-sulfonic acid (PyS), quinoline-8-sulfonic acid (QS), and 2-aminobenzenesulfonic acid (ABS), that have the basic taurine structure (N-C-C-S) partially in a semirigid unsaturated ring structure stimulate the phosphorylation of the ∼44-Kd protein. Due to the unsaturated ring structure, these analogs of taurine have a net neg. charge at physiol. pH and are not zwitterions. When PyS, QS, or ABS was titrated in the presence of a fixed concentration of taurine (10 mM), there was a competitive relation even through their electronic nature is quite different than that of taurine. The combination of QS plus PyS (1:5) appears to progress through a transition from being synergistic at low concentrations of the fixed ratio mixture, additive at 50% saturation, and finally antagonistic at high concentration of the fixed ratio mixture

Journal of Cardiovascular Pharmacology 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, COA of Formula: C5H5NO3S.

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

Lombardini, John B. published the artcileEffects of taurine and taurine analogs on the phosphorylation of a 44 kDa protein present in a mitochondrial subfraction of the rat heart: partial characterization of the 44 kDa phosphoprotein, Quality Control of 636-73-7, the publication is Journal of Molecular and Cellular Cardiology (1994), 26(12), 1675-89, database is CAplus and MEDLINE.

Recent studies suggest that taurine (2-aminoethanesulfonic acid) is involved in the regulation of protein phosphorylation in excitable tissues such as the retina, brain and heart. To determine the structural requirements for the effect of taurine on the phosphorylation of a 44 kDa protein(s), a series of taurine analogs were tested in an in vitro assay using a subcellular mitochondrial fraction of rat heart. Inhibitors of the phosphorylation of the 44 kDa protein include taurine and close structural analogs of taurine such as aminoethylhydrogen sulfate and α-sulfo-β-alanine. Secondary amines with the taurine structure partially locked into a saturated 5-membered ring such as (±)piperidine-3-sulfonic acid and 1,2,3,4-tetrahydroquinoline-8-sulfonic acid also possess inhibitory activity. Sulfone analogs of taurine such as 2-aminoethylmethylsulfone, a non-restricted taurine analog with maximal conformational flexibility about its amino and sulfone moieties, and (±)3-aminotetrahydrothiopyran-1,1-dioxide, an analog containing the sulfone moiety in a six-membered ring structure, were more potent inhibitors of phosphorylation than taurine despite the fact that the sulfone moiety is neither an isosteric nor isoelectronic substitution for the sulfonic acid moiety. The results of this study indicate that the inhibition of the phosphorylation of the 44 kDa protein in a rat heart mitochondrial fraction is relatively specific for the taurine structure. Two analogs of taurine with unsaturated rings containing a primary sulfonic acid and a secondary amine. Pyridine-3-sulfonic acid and quinoline-8-sulfonic acid, were observed to be stimulators of the phosphorylation of the 44 kDa protein. In addition, 2-aminobenzenesulfonic acid also stimulated phosphorylation. Phase separation experiments with Triton X-114 suggest that the 44 kDa phosphoprotein is a soluble protein and not an integral membrane protein of the mitochondria. Phosphate incorporation into specific amino acids was determined by two-dimensional electrophoresis on celluloses plates and was found exclusively in the serine residues.

Journal of Molecular and Cellular Cardiology 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, Quality Control of 636-73-7.

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

Li, Yan published the artcilePalladium-catalyzed cross-coupling of benzyltitanium(IV) reagents with aryl fluorides, Name: 4-Fluoropicolinonitrile, the publication is Monatshefte fuer Chemie (2022), 153(2), 193-199, database is CAplus.

The first palladium-catalyzed cross-coupling between benzyltitanium(IV) reagents with aryl fluorides is reported. A variety of diarylmethanes can be prepared in good to excellent yields by the catalyst system of PdCl₂(dppf)₂ associated with 1-[2-(di-tert-butylphosphanyl)phenyl]-4-methoxypiperidine. This reaction offered a highly efficient approach to diarylmethanes that are commonly found in life-changing drug mols.

Monatshefte fuer Chemie published new progress about 847225-56-3. 847225-56-3 belongs to pyridine-derivatives, auxiliary class Pyridine,Fluoride,Nitrile, name is 4-Fluoropicolinonitrile, and the molecular formula is C6H3FN2, Name: 4-Fluoropicolinonitrile.

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

Kiselyov, Alexander S. published the artcileReaction of N-fluoropyridinium salts with Wittig reagents: a novel and convenient approach to symmetric trans-olefins, Category: pyridine-derivatives, the publication is Tetrahedron Letters (1994), 35(48), 8951-4, database is CAplus.

N-fluoropyridinium salts react with Wittig reagents containing electron-withdrawing groups to give olefins in 47-83% yield. The mechanism of this conversion is believed to involve single-electron transfer from Wittig reagent to N-fluoropyridinium cation.

Tetrahedron Letters published new progress about 107263-95-6. 107263-95-6 belongs to pyridine-derivatives, auxiliary class Fluorination reagent, name is 1-Fluoropyridiniumtriflate, and the molecular formula is C6H5F4NO3S, Category: pyridine-derivatives.

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

Kiselyov, Alexander S. published the artcileA novel three-component reaction of N-fluoropyridinium salts: a facile approach to imidazo[1,2-a]pyridines, Formula: C6H5F4NO3S, the publication is Tetrahedron Letters (2005), 46(26), 4487-4490, database is CAplus.

The reaction of N-fluoropyridinium triflates I (R¹ = H, 2-Me, 4-Me₂CH, 2-Ph, 3-Cl, etc.) with isonitriles R²NC (R² = Me₂CH, Me₃C, EtO₂CH₂, cyclohexyl, Ph, PhCH₂, etc.) in acetonitrile or propionitrile in the presence of NaBH(OAc)₃ led to the formation of the corresponding imidazo[1,2-a]pyridines II (R³ = Me, Et) in 44-73% yields. The proposed reaction mechanism involves the intermediate formation of a highly reactive carbene species and apparent reduction of the pyridinium intermediate with NaBH(OAc)₃ to yield the targeted heterocycles.

Tetrahedron Letters published new progress about 107263-95-6. 107263-95-6 belongs to pyridine-derivatives, auxiliary class Fluorination reagent, name is 1-Fluoropyridiniumtriflate, and the molecular formula is C6H5F4NO3S, Formula: C6H5F4NO3S.

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

Guven, Alaattin published the artcileAcidity study on 3-substituted pyridines, Recommanded Product: Pyridine-3-sulfonic acid, the publication is International Journal of Molecular Sciences (2005), 6(11), 257-275, database is CAplus.

A comprehensive theor. study for the protonation of some 3-substituted pyridines has been carried out in aqueous solution (ε=78.4) by semi empirical AM1 method in MOPAC2000 and PM5 method in MOPAC2002. Solvent effect was accounted for implicitly by means of the conductor like screening model (COSMO). The acidity constants of these pyridine derivatives have been calculated The tautomeric and/or conformational equilibrium for these compounds, where available, were also taken into account to find out the mol fractions of the species in aqueous media. The results obtained from the calculations were compared with the available exptl. values, and the results indicate a considerable agreement with available exptl. data.

International Journal of Molecular Sciences 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, Recommanded Product: Pyridine-3-sulfonic acid.

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

Feibelman, Peter J. published the artcileWhat Limits Turnover Number in NH₃ Synthesis on a PNP Pincer Molecule?, SDS of cas: 338800-13-8, the publication is Comments on Inorganic Chemistry (2014), 34(1-2), 3-16, database is CAplus.

Abiol. NH₃ synthesis under mild conditions on a PNP [=2,6-bis(di-tert-butyl-phosphinomethyl)pyridine] pincer chelating an Mo(N₂)₃ group has been reported and attributed to a catalytic cycle wherein only the equatorial N₂ is reduced. The present calculations suggest that reduction of axial N₂ ligands was the reason the cycle ended after production of 23 equivalent of NH₃. NH₃ detachment from axial NNH₃ initiates a terminal reaction pathway by leaving an axial nitrido N behind on the Mo. The trans influence of the strong axial nitride bond causes the second axial N₂ to detach from the Mo, with N-Mo-N₂ remaining as a non-catalytic, pincer-chelated group.

Comments on Inorganic Chemistry 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 C23H43NP2, SDS of cas: 338800-13-8.

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

El-Assal, Mona Ibrahim published the artcileNano-sponge novel drug delivery system as carrier of anti-hypertensive drug, Computed Properties of 89076-64-2, the publication is International Journal of Pharmacy and Pharmaceutical Sciences (2019), 11(10), 47-63, database is CAplus.

The study was designed to prepare Nano-sponge formulation loaded with nifedipine. Studying parameters which affecting the formulas in addition to pharmacokinetics and toxicity tests. Nine Nano-sponge formulations were prepared by the solvent evaporation technique. Different ratios of polymer ethylcellulose, COpolymers β-cyclodextrin and hydroxypropyl β-cyclodextrin in addition to solubilizing agent polyvinyl alc. were used. Thermal anal., X-ray powder diffraction (XRPD), shape and surface morphol., particle size, %production yield, %porosity, % swelling, and % drug entrapment efficiency of Nano-sponge were examined Release kinetic also studied beside comparison of pharmacokinetic parameters of the optimum choice formula and marketed one in addition to Toxicol. consideration. Particle size in the range of 119.1 nm to 529 nm which were increased due to the increase in the concentration of polymer to the drug. Nano-sponge revealed porous, spherical nature. Increased in the drug/polymer molar ratios (1:1 to 1:3) may increase their % production yield ranged from 62.1% to 92.4%. The drug content of different formulations was in the range of 77.9% to 94.7%, and entrapment efficiency was in the range of 82.72 % to 96.63%. Drug released in controlled sustained pattern and followed Higuchi, s diffusion mechanism. Pharmacokinetic parameters of optimized formula showed significant higher maximum plasma drug concentration, area under plasma concentration-time curve, volume of distribution and mean residence time. Nano-sponge loaded drug proved biol. safety at low concentrations Nano-sponge drug delivery system has showed small Nano size, porous with controlled drug release and significant-high plasma drug concentration that improved solubility, drug bioavailability and proved safety.

International Journal of Pharmacy and Pharmaceutical Sciences published new progress about 89076-64-2. 89076-64-2 belongs to pyridine-derivatives, auxiliary class Pyridine,Nitro Compound,Benzene, name is 5-Nitro-2-phenylpyridine, and the molecular formula is C11H8N2O2, Computed Properties of 89076-64-2.

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

El Ali, Bassam published the artcileRh₆(CO)₁₆-H₃PW₁₂O₄₀-catalyzed one pot hydroformylation-cyclotrimerization of cyclohexene and cyclopentene to 2,4,6-trisubstituted 1,3,5-trioxanes, Recommanded Product: Pyridine-3-sulfonic acid, the publication is Journal of Molecular Catalysis A: Chemical (2003), 203(1-2), 53-58, database is CAplus.

One-pot hydroformylation-cyclotrimerization of cyclopentene and cyclohexene was selectively catalyzed by Rh₆(CO)₁₆ and H₃PW₁₂O₄₀·xH₂O (HPA-W₁₂) in THF at 40 atm (CO/H₂ = 1/1) and afforded 2,4,6-tris(cycloalkyl)-1,3,5-trioxanes as major products along with the corresponding aldehydes.

Journal of Molecular Catalysis A: Chemical 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, Recommanded Product: Pyridine-3-sulfonic acid.

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

Christophe, Bernard published the artcileOccurrence of early after depolarization under healthy or hypertrophic cardiomyopathy conditions in the human ventricular endocardial myocyte: In silico study using 109 torsadogenic or non-torsadogenic compounds, Recommanded Product: Dimethyl 2,6-dimethyl-4-(2-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylate, the publication is Toxicology and Applied Pharmacology (2022), 115914, database is CAplus and MEDLINE.

The goal of the CiPA initiative (Comprehensive in vitro Proarrhythmia Assay) was to assess a more accurate prediction of new drug candidate proarrhythmic severe liabilities such as torsades de pointes, for example. This new CiPA paradigm was partly based on in silico reconstruction of human ventricular cardiomyocyte action potential useful to identify repolarization abnormalities such early afterdepolarization (EAD), for example. Using the ToR-ORd algorithm (Tomek-Rodriguez-O’Hara-Rudy dynamic model), the aim of the present work was (i) to identify intracellular parameters leading to EAD occurrence under healthy and hypertrophic cardiomyopathy (HCM) conditions and (ii) to evaluate the prediction accuracy of compound torsadogenic risk based on EAD occurrence using a large set of 109 torsadogenic and non-torsadogenic compounds under both exptl. conditions. In silico results highlighted the crucial involvement of Ca++ handling in the ventricular cardiomyocyte intracellular subspace compartment for the initiation of EAD, demonstrated by a higher amplitude of Ca++ release from junctional sarcoplasmic reticulum to subspace compartments (Jrel) measured at EAD take-off voltage in the presence vs. the absence of EAD initiated either by high IKr inhibition or by high enough concentration of a torsadogenic compound under both exptl. conditions. Under healthy or HCM conditions, the prediction accuracy of the torsadogenic risk of compound based on EAD occurrence was observed to be 61 or 92%, resp. This high accuracy under HCM conditions was discussed regarding its usefulness for cardiac safety pharmacol. at least at early drug screening/preclin. stage of the drug development process.

Toxicology and Applied Pharmacology 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