Tag: M.W=100-150

Berg, Ulf published the artcileTransition State Structural Variations in the Menshutkin Reaction. A Computational Study of Steric and Electronic Substituent Effects, COA of Formula: C6H8N2, the publication is Journal of Organic Chemistry (1995), 60(7), 1975-80, database is CAplus.

Transition structures for the gas phase S_N2 reactions of substituted pyridines with Me chloride, bromide, and iodide, resp., have been localized by the AMPAC program using the AM1 Hamiltonian. The reactions are strongly endothermic (ΔE ≈ 40-60 kcal/mol) and have activation barriers of ca. 70 kcal/mol, and the calculated order of leaving group (X) abilities is I < Br < Cl. The carbon-nitrogen bond is longer for the more reactive leaving group. The structural parameters are relatively insensitive to substitutions in the pyridine ring. Increasing the steric strain in the ortho position (Me to tert-Bu or 2,6-dimethyl) leads to looser and earlier transition states, whereas substitution with electron-withdrawing groups in the para position has very little effect on the transition structure. Solvent effects were briefly mimicked by means of a dipole placed on the N· · ·C· · ·X axis with the pos. charge pointing toward X. This results in a decrease of the activation barrier, a less endothermic reaction, earlier transition state, and a larger neg. charge on X. The consequences of steric effects in this reaction are discussed.

Journal of Organic Chemistry 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, COA of Formula: C6H8N2.

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

Bursavich, Matthew G. published the artcileNovel benzofuran-3-one indole inhibitors of PI3 kinase-α and the mammalian target of rapamycin: hit to lead studies, Application of 2-Pyridinylboronic acid, the publication is Bioorganic & Medicinal Chemistry Letters (2010), 20(8), 2586-2590, database is CAplus and MEDLINE.

A series of benzofuran-3-one indole phosphatidylinositol-3-kinases (PI3K) inhibitors identified via HTS has been prepared The optimized inhibitors possess single digit nanomolar activity against p110α (PI3K-α), good pharmaceutical properties, selectivity vs. p110γ (PI3K-γ), and tunable selectivity vs. the mammalian target of rapamycin (mTOR). Modeling of compounds I (R = H; CH₂CH₂CH₂NMe₂) in homol. models of PI3K-α and mTOR supports the proposed rationale for selectivity. Compounds show activity in multiple cellular proliferation assays with signaling through the PI3K pathway confirmed via phospho-Akt inhibition in PC-3 cells.

Bioorganic & Medicinal Chemistry Letters 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, Application of 2-Pyridinylboronic acid.

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

Billingsley, Kelvin L. published the artcileA general and efficient method for the Suzuki-Miyaura coupling of 2-pyridyl nucleophiles, Formula: C5H6BNO2, the publication is Angewandte Chemie, International Edition (2008), 47(25), 4695-4698, database is CAplus and MEDLINE.

One of the most general systems for the cross-coupling of aryl and heteroaryl bromides and chlorides R¹X (R¹ = 4-n-BuC₆H₄, 2,5-Me₂C₆H₃, 3-pyridyl, 5-pyrimidyl, 4-isoquinolinyl, etc.; X = Cl, Br) with 2-pyridyl-derived nucleophiles R²B(OCHMe₂)₃Li [R² = 2-pyridyl, 5-fluoro-2-pyridyl, 6-methoxy-2-pyridyl, 6-(1,3-dioxolan-2-yl)-2-pyridyl] with formation of 2-aryl-substituted pyridines has been developed. The best catalysts were comprised from [Pd₂(dba)₃] and either di-Ph or di(tert-butyl) phosphine oxide.

Angewandte Chemie, International Edition 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, Formula: C5H6BNO2.

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

Calugi, Lorenzo published the artcileSuzuki and Heck Processes for the Synthesis of New Anthraquinone-Based Glycoconjugated Dyes, Safety of 2-Pyridinylboronic acid, the publication is ChemistrySelect (2018), 3(8), 2235-2239, database is CAplus.

Starting from a bromo-anthraquinone dye, different aryl- and styril- derivates are obtained following Suzuki and Heck procedures. Bathochromic shifts are displayed for the products, if compared to the starting anthraquinone dye. Two of these dyes, coming from either the Suzuki and the Heck processes, have been glycosylated with a piperazinyl-lactose derivative, so that two naturalized species are finally obtained. Therefore, the disperse chromophores were transformed in water soluble direct species. These kinds of dyes allow to avoid azo- structures, that are object of growing criticism in the European Union due to their environmental impact.

ChemistrySelect 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, Safety of 2-Pyridinylboronic acid.

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

Shimeno, Hiroshi published the artcileInhibition of rat liver tryptophan pyrrolase activity and elevation of brain tryptophan concentration by administration of DL-α-amino-β-pyridinepropanoic acid (pyridylalanine) analogs, Computed Properties of 18437-58-6, the publication is Journal of Enzyme Inhibition (1987), 2(1), 57-66, database is CAplus and MEDLINE.

Single doses of DL-α-amino-β-(2-pyridine)propanoic acid (2-PA, 100 mg/kg) decreased the holoenzyme and apoenzyme activities of rat liver tryptophan pyrrolase (TP) and increased brain tryptophan, serotonin (5-HT) and 5-hydroxyindole-3-ylacetic acid concentrations 2-PA had no inhibitory effect on either of the enzyme activities in vitro, but its expected metabolites were effective. Single doses of DL-α-amino-β-(3-pyridine)propanoic acid (3-PA, 100 mg/kg) decreased only the holoenzyme activity and elevated brain tryptophan and its metabolites levels in rats. 3-PA and its metabolite, 3-pyridylpyruvate, inhibited only the holoenzyme activity in vitro. DL-α-Amino-β-(4-pyridine)propanoic acid (4-PA) caused changes in liver TP (holo- and apoenzyme forms) activity and brain tryptophan concentration only after repeated administration (100 mg/kg/day). 4-PA was a weak inhibitor of the holoenzyme, but its metabolites apparently inhibited the holo- and apoenzyme activities in vitro. These findings suggest that PA analogs (and(or) their metabolites) increased brain tryptophan (and hence 5-HT synthesis) by directly inhibiting liver TP activity.

Journal of Enzyme Inhibition 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 C8H11NO, Computed Properties of 18437-58-6.

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

Thomas, Michael published the artcileScaffold-Hopping Strategy on a Series of Proteasome Inhibitors Led to a Preclinical Candidate for the Treatment of Visceral Leishmaniasis, Product Details of C5H6BNO2, the publication is Journal of Medicinal Chemistry (2021), 64(9), 5905-5930, database is CAplus and MEDLINE.

There is an urgent need for new treatments for visceral leishmaniasis (VL), a parasitic infection which impacts heavily large areas of East Africa, Asia, and South America. We previously reported on the discovery of GSK3494245/DDD01305143 (1) as a preclin. candidate for VL and, herein, we report on the medicinal chem. program that led to its identification. A hit from a phenotypic screen was optimized to give a compound with in vivo efficacy, which was hampered by poor solubility and genotoxicity. The work on the original scaffold failed to lead to developable compounds, so an extensive scaffold-hopping exercise involving medicinal chem. design, in silico profiling, and subsequent synthesis was utilized, leading to the preclin. candidate. The compound was shown to act via proteasome inhibition, and we report on the modeling of different scaffolds into a cryo-EM structure and the impact this has on our understanding of the series’ structure-activity relationships.

Journal of Medicinal Chemistry 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 C12H10O4S, Product Details of C5H6BNO2.

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

Martinez, Kristina published the artcilePhotophysics of Ru(II) complexes with hydroxylated diimine ligands: Photoinduced electron/proton transfer to anthraquinone, Name: 2-Pyridinylboronic acid, the publication is Polyhedron (2021), 115376, database is CAplus.

This manuscript reports the reaction of the ³MLCT excited states of two luminescent chromophores, [(bpy)₂Ru(OHbpy)]²⁺ and [(bpy)₂Ru(OMebpy)]²⁺ (bpy = 2,2â€?bipyridine, OHbpy = 4-hydroxy-2,2â€?bipyridine, OMebpy = 4-methoxy-2,2â€?bipyridine), with anthraquinone (AQ). A series of luminescence, electrochem., spectrophotometric and transient absorption studies were done in order to determine free energies for the potential reaction paths between the photoexcited complexes and AQ. For the OMebpy complex, only excited state electron transfer (ET*) from the ³MLCT state of the complex to AQ was possible. However, for the OHbpy complex, the excited state could react with AQ via a variety of pathways including excited state electron transfer, ET*, excited state proton transfer (PT*) and excited state proton coupled electron transfer (PCET*). The thermodn. anal. revealed that, for the OHbpy complex PT* was very endergonic and not a viable reaction pathway, however both ET* and PCET* could occur. Luminescence quenching studies revealed that both the OHbpy and the OMebpy excited complexes reacted with AQ (k_q âˆ?10⁹ M^-1s^-1 for both). Transient absorption anal. showed that, for the OMebpy complex, no photoproducts escaped the encounter complex associated with the quenching reaction. The result is consistent with strong electrostatic association of the 3+/1- encounter complex. For the OHbpy complex transient absorption results clearly show the formation of PCET* products from the encounter complex. The result represents one of a small number of examples of excited states of chromophores reacting via proton coupled electron transfer within an encounter complex.

Polyhedron 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, Name: 2-Pyridinylboronic acid.

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

Kolekar, Yuvraj A. published the artcilePd-Catalyzed Oxidative Aminocarbonylation of Arylboronic Acids with Unreactive Tertiary Amines via C-N Bond Activation, HPLC of Formula: 197958-29-5, the publication is Journal of Organic Chemistry (2021), 86(20), 14028-14035, database is CAplus and MEDLINE.

An efficient synthesis of tertiary amides from aryl boronic acids and inert tertiary amines through the oxidative carbonylation via C(sp³)-N bond activation is presented. This protocol significantly restricts the homocoupling biarylketone product. It involves the use of a homogeneous PdCl₂/CuI catalyst and a heterogeneous Pd/C based catalyst, which promotes C(sp³)-N bond activation of tertiary amines with aryl boronic acids. This process represents a ligand-free, base-free, and recyclable catalyst along with an ideal oxidant like mol. oxygen.

Journal of Organic Chemistry 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, HPLC of Formula: 197958-29-5.

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

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