Month: December 2022

Rombouts, Frederik J. R. published the artcileDiscovery of N-(4-[¹⁸F]Fluoro-5-methylpyridin-2-yl)isoquinolin-6-amine (JNJ-64326067), a New Promising Tau Positron Emission Tomography Imaging Tracer, Synthetic Route of 18437-58-6, the publication is Journal of Medicinal Chemistry (2019), 62(6), 2974-2987, database is CAplus and MEDLINE.

In Alzheimer’s disease, the d. and spread of aggregated tau protein track well with neurodegeneration and cognitive decline, making the imaging of aggregated tau a compelling biomarker. A structure-activity relationship exploration around an isoquinoline hit, followed by an exploration of tolerated fluorination positions, allowed us to identify 9 (JNJ-64326067), a potent and selective binder to aggregated tau with a favorable pharmacokinetic profile and no apparent off-target binding. This was confirmed in rat and monkey positron emission tomog. studies using [¹⁸F]9.

Journal of Medicinal 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, Synthetic Route of 18437-58-6.

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

Guo, Beibei published the artcileSelective α-Deuteration of Cinnamonitriles using D₂O as Deuterium Source, Quality Control of 91-02-1, the publication is Advanced Synthesis & Catalysis (2022), 364(1), 179-186, database is CAplus.

The selective α-deuteration of α,β-unsaturated nitriles using the strong base t-BuOK or a metal-ligand cooperative Ru pincer catalyst was described. With D₂O as deuterium source and glyme as solvent at 70°C, t-BuOK is an efficient catalyst for deuteration at the α-C(sp²) position of cinnamonitriles, providing access to a broad range of deuterated derivatives in good to excellent yields and with very high levels of deuterium incorporation. While the t-BuOK-catalyzed protocol does not tolerate base-sensitive functional groups, cinnamonitrile derivatives containing a benzylic bromide or ester moiety were deuterated in excellent yields using Milstein’s ruthenium PNN pincer catalyst. Moreover, the activity for H/D exchange of the metal-ligand cooperative Ru catalyst was found to be significantly higher than that of t-BuOK, allowing reactions to proceed well even at room temperature A mechanistic proposal is put forward that involves deprotonation of the cinnamonitrile α-CH position when using t-BuOK as catalyst, whereas H/D exchange catalysis with the Ru PNN pincer likely proceeds via (reversible) oxa-Michael addition of D₂O.

Advanced Synthesis & Catalysis 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, Quality Control of 91-02-1.

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

Vrijdag, Johannes L. published the artcileTowards New Tricyclic Motifs: Intramolecular C-H Arylation as the Key Step in a Formal [3+3] Cyclocondensation Strategy, Category: pyridine-derivatives, the publication is European Journal of Organic Chemistry (2017), 2017(11), 1465-1474, database is CAplus.

Tricyclic scaffolds structurally related to the well-known benzodiazepine class of drugs show diverse biol. activities strikingly different from those of their benzodiazepine counterparts. Interested by this scaffold-hopping perspective, we previously developed a continuous-flow method for the conversion of benzodiazepinediones into oxazoloquinolinones. Attempted extension of this synthetic route to the corresponding oxazolonaphthyridinone scaffolds met with limited success, however. This encouraged us to develop a different approach to pyridine-based tricyclic motifs. In line with our interest in scaffold hopping, in this paper authors describe a general, convergent [3+3] cyclocondensation approach to [1,3]oxazolo[4,5-c]-1-naphthyridin-4(5H)-ones. The key synthetic steps in this approach are: (1) the construction of an amide linkage connecting two peripheral heterocycles; and (2) a palladium-catalyzed intramol. C-H arylation to complete the tricyclic scaffold.

European Journal of Organic 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 C8H10O2, Category: pyridine-derivatives.

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

Pang, Yuan-Ping published the artcileSmall molecules showing significant protection of mice against botulinum neurotoxin serotype A, COA of Formula: C6H5F4NO3S, the publication is PLoS One (2010), 5(4), No pp. given, database is CAplus and MEDLINE.

Botulinum neurotoxin serotype A (BoNTA) causes a life-threatening neuroparalytic disease known as botulism that could afflict large, unprotected populations if the toxin were employed in an act of bioterrorism. Current post-exposure therapy is limited to symptomatic treatment or passive immunization that is effective for treating infant botulism at a cost of US $45,300 per treatment regimen. Antibodies can neutralize the extracellular but not the intracellular BoNTA. Moreover, antibody production, storage, and administration in a mass casualty scenario pose logistical challenges. Alternatively, small-mol. inhibitors of BoNTA endopeptidase (BoNTAe) are sought to antagonize the extracellular or intracellular toxin. While several such mols. reportedly demonstrated efficacy in protecting cells against BoNTA, there is scant information to show that small mols. can significantly protect mammals against BoNTA. Herein the authors report the development of effective small-mols. BoNTAe inhibitors with promising in vivo pharmacokinetics. One such mol. has an in vivo half-life of 6.5 h and is devoid of obvious sign of toxicity. Pre-treatment with this mol. at 2 mg/kg protected 100% and 70% of treated mice against BoNTA at 5 times of its median-LD during the periods of 2 and 4 half-lives of the inhibitor, resp. In contrast, 40% and 0% of untreated mice survived during the resp. periods. Similar levels of protection were also observed with two other small mols. These results demonstrate that small mols. can significantly protect mice against BoNTA and support the pursuit of small-mol. antagonists as a cost-effective alternative or as an adjunct to passive immunity for treating botulism.

PLoS One 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, COA of Formula: C6H5F4NO3S.

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

Boelter, Scott D. published the artcileEvaluation of Bis(phosphine) Ligands for Ethylene Oligomerization: Discovery of Alkyl Phosphines as Effective Ligands for Ethylene Tri- and Tetramerization, Quality Control of 338800-13-8, the publication is Organometallics (2020), 39(7), 967-975, database is CAplus.

Fifty-three bis(phosphines) were evaluated as ligands for chromium-catalyzed ethylene tetramerization in a high-throughput reactor. Ligands previously reported in the literature gave high activities with expected selectivities when evaluated under our reactor conditions. While the majority of ligands evaluated gave low activity catalysts that produced mostly high-d. polyethy1613170629lene (HDPE), alkyl phosphines were unexpectedly identified as a promising ligand class. In particular, the MeDuPhos ligand led to an active catalyst that produced 81.8 weight % α-olefins (50.0 wt % 1-octene, 31.8 wt % 1-hexene) and 3.5 wt % HDPE, approaching the selectivity of the state-of-the-art i-Pr-PNP ligand.

Organometallics 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, Quality Control of 338800-13-8.

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

Yadav, Rakhee published the artcileRole of calcium ion channels and cytoskeletal proteins in Thorium-232 induced toxicity in normal human liver cells (WRL 68) and its validation in swiss mice, Application In Synthesis of 21829-25-4, the publication is Chemosphere (2022), 288(Part_2), 132557, database is CAplus and MEDLINE.

Hepatic disorders reported in humans exposed to Thorium-232 (Th-232) rationalizes the present study investigating the toxicol. response of normal human liver cells (WRL 68) and its validation in Swiss mice. Cell count anal. of WRL 68 cells-treated with Th-nitrate (1-200μM) estimated IC₅₀ of ∼24μM (at 24 h) and 35μM (at 48 h). Anal. of cell viability (trypan blue assay) showed the IC₅₀ of ∼172μM. Phase contrast bright-field microscopy revealed Th-induced morphol. changes and cell-released microvesicle-like structures in extracellular space. Th-estimation by ICP-MS (Inductively-coupled plasma mass-spectrometry) showed uptake of Th by cells as a function of concentration and incubation time. Employing DTPA as a chelating agent in cell harvesting solution, cell-internalized/strongly-bound Th was estimated to be ∼42% of total incubated Th. Th-uptake studies in the presence of ion-channel specific inhibitors (e.g. nifedipine, thapsigargin) revealed the role of plasma membrane calcium channels and cytoplasmic calcium in modulating the Th-uptake. Transmission electron microscopy of Th-treated cells showed cell-derived extracellular vesicles, alterations in the shape and size of nucleus and mitochondria as well as cytoplasmic inclusions. The order of Th accumulation in various sub-cellular protein fractions was found to be as cytoskeleton (43%) > cytoplasmic (15%) > chromatin (7%) > nuclear (5%) & membrane (5%). Immunofluorescence anal. of WRL 68 cells showed that Th significantly altered the expression of cytoskeleton proteins (F-actin and keratin), which was further validated in liver tissues of Swiss mice administered with Th-232. Findings herein highlight the role of calcium channels and cytoskeleton in Th-induced toxicity. Keywords: Thorium toxicity; Liver cells; Calcium channels; Sub-cellular targets, Cytoskeleton; Swiss Mice.

Chemosphere 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 C8H6KNO4S, Application In Synthesis of 21829-25-4.

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

Kumar Mudi, Prafullya published the artcileHead-to-Tail interlocking aromatic rings of a hydrazine functionalized Schiff base for the development of Nano-aggregates with blue emission: Structural and spectroscopic characteristics, Recommanded Product: Phenyl(pyridin-2-yl)methanone, the publication is Journal of Molecular Liquids (2021), 117193, database is CAplus.

We report the synthesis, physicochem. and morphol. characterization, supramol. interactions and aggregation-induced blue emission of a newly developed Schiff base, 1,2-bis(phenyl(pyridin-2-yl)methylene)hydrazine (P18). The compound was synthesized through a condensation reaction between hydrazine and 2-benzoylpyridine under reflux in ethanol. The photophys. behavior of the Schiff base was studied in both monomeric and aggregated forms. Interestingly, the mol. aggregate showed a significant blue shift with ∼ 20 fold higher fluorescence intensity with lifetime, 0.99 ns in the aqueous phase than that of monomeric form, attributed to the development of J-type aggregation. The crystal structure, C-H···π and π…π interactions, were enumerated to decipher the nature of aggregation. The Schiff base consisting of four aromatic rings (two pyridine and two Ph rings) displayed a short C-H···π and a long distant π···π interactions causing a head-to-tail type interlocking of aromatic rings. Energy framework anal. confirmed the predominance of dispersive forces (-192.4 kJ/mol) to the cluster of mols., thus playing a significant role in the restriction of intramol. motion of the aromatic rings of P18. A restrain on the rotational probability of = N-N = and Ar-C- bonds leads to an enhancement of an intense fluorescence property of nano-aggregate with blue light emission in solid state. The propagation of the rectangular-shaped monomeric probe in the nano-aggregate with an average hydrodynamic size of 270(±3) nm was established with field emission SEM, dynamic scattering light, and electron dispersive X-ray spectral anal.

Journal of Molecular Liquids 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

Goni, A. Md. published the artcileCoordination nature of europium(III) with ^tBuPNP (2,6-bis(di-tert-butylphosphinomethyl) pyridine) ligand, COA of Formula: C23H43NP2, the publication is Inorganica Chimica Acta (2013), 645-648, database is CAplus.

The reaction of 2,6-bis(di-tert-butylphosphinomethyl)pyridine (PNP) with hydrated Eu(III) chloride yields a novel complex, dichlorotriaqua[2,6-bis(di-tert-butylphosphorylmethyl)pyridine]europium(III) chloride. The complex crystallizes as a dihydrate. IR, ¹H and ³¹P NMR spectroscopic studies were undertaken along with x-ray diffraction studies for structural elucidation. The solid state structure of the compound reveals the insertion of O atoms in the inner coordination sphere bridging P and Eu atoms. The metal center is a seven coordinate system ligated by two chloride ligands, three H₂O ligands and two O atoms from the oxidized phosphine moiety of the PNP ligand. The N atom of the pyridine unit of the ligand is not coordinated to the metal center.

Inorganica Chimica Acta 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, COA of Formula: C23H43NP2.

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

Cotton, F. Albert published the artcileSynthesis and x-ray structure of two relatively air-stable chromium(II) 3-pyridinesulfonate compounds, Safety of Pyridine-3-sulfonic acid, the publication is Polyhedron (1992), 11(19), 2475-81, database is CAplus.

[Cr(pySO₃)₂(H₂O)₂]_n (I; pySO₃H = 3-pyridinesulfonic acid) and Cr(pySO₃)₂(py)₄ (II) were prepared and crystal structures determined I crystallizes as monoclinic, space group P2₁/c in an extended structure, a 7.723(1), b 12.995(4), c 7.276(3) Å, β 100.24(2)°, Z = 2, R = 0.032, R_w = 0.046. II possesses a mol. structure and crystallizes as monoclinic, space group C2/c, a 17.084(4), b 11.031(3), c 17.828(7) Å, β 112.02(2)°, Z = 4, R = 0.031, R_w = 0.043. The coordination about the Cr atoms is, in both cases, highly distorted. Both compounds are relatively stable towards O in the solid state, especially I.

Polyhedron 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

Schempp, Tabitha T. published the artcileA General Strategy for the Construction of Functionalized Azaindolines via Domino Palladium-Catalyzed Heck Cyclization/Suzuki Coupling, Name: 2-Bromopyridin-3-amine, the publication is Organic Letters (2017), 19(13), 3616-3619, database is CAplus and MEDLINE.

The preparation of substituted azaindolines utilizing a domino palladium-catalyzed Heck cyclization/Suzuki coupling is described. The approach is amenable for the construction of all four azaindoline isomers. A range of functional groups such as esters, amides, ketones, sulfones, amines, and nitriles are all tolerated under the reaction conditions.

Organic Letters 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, Name: 2-Bromopyridin-3-amine.

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