Day: October 21, 2022

Safety of 4-AcetylpyridineIn 2022 ,《Thioamide synthesis via copper-catalyzed C-H activation of 1,2,3-thiadiazoles enabled by slow release and capture of thioketenes》 was published in Organic Chemistry Frontiers. The article was written by Lu, Changhui; Li, Xiaohong; Chang, Shunqin; Zhang, Yuqi; Xing, Donghui; Wang, Shuo; Lin, Yueping; Jiang, Huanfeng; Huang, Liangbin. The article contains the following contents:

A Cu-catalyzed thioacylation of amines via a C-H activation/coordinated stabilization protocol to ensure the slow-release of thioketenes, which are captured by various amines to afford thioamides was developed. This method was characterized by its simplicity, efficiency and broad substrate scope in both 1,2,3-thiadiazoles and amines. Its versatility was further illustrated by the late-stage thioamidation of N-containing drugs, peptides, catalysts, and ligands. Mechanism studies demonstrate that the active Cu(I) species was formed via the reduction of Cu(II) during the induction period, and the rate-determining step was the C-H activation of 1,2,3-thiadiazole. In the part of experimental materials, we found many familiar compounds, such as 4-Acetylpyridine(cas: 1122-54-9Safety of 4-Acetylpyridine)

4-Acetylpyridine(cas: 1122-54-9) belongs to pyridine. Pyridines, quinolines, and isoquinolines have found a function in almost all aspects of organic chemistry. Pyridine has found use as a solvent, base, ligand, functional group, and molecular scaffold. As structural elements, these moieties are potent electron-deficient groups, metal-directing functionalities, fluorophores, and medicinally important pharmacophores. Safety of 4-Acetylpyridine

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

《Chiral Hexahalogenated 4,4′-Bipyridines》 was written by Mamane, V.; Peluso, P.; Aubert, E.; Cossu, S.; Pale, P.. Name: 5-Bromo-2-chloropyridineThis research focused ontrihalopyridine dimerization; bipyridinedione regioselective halogenation copper Finkelstein reaction catalyst; bipyridine hexahalogenated preparation kinetic resolution; chiral hexahalogenated bipyridine preparation. The article conveys some information:

The preparation of 27 isomers of chiral hexahalogeno-4,4′-bipyridines by means of two complementary methods is described. The first one is convergent and based on the LDA-induced 4,4′-dimerization of trihalopyridines, whereas the second method is divergent and achieved through regioselective halogenation reactions of 4,4′-bipyridine-2,2′-diones. Iodine in 2,2′-positions of the 4,4′-bipyridines was introduced by a copper-catalyzed Finkelstein reaction (Buchwald procedure) performed on 2,2′-dibromo derivatives Selected compounds of this new family of atropisomeric 4,4′-bipyridines were enantiosepd. by high performance liquid chromatog. on chiral stationary phases, and the absolute configurations of the separated enantiomers were assigned by using X-ray diffraction anal. The latter revealed that various halogen bond types are responsible for crystal cohesion. In the experiment, the researchers used 5-Bromo-2-chloropyridine(cas: 53939-30-3Name: 5-Bromo-2-chloropyridine)

5-Bromo-2-chloropyridine(cas: 53939-30-3) belongs to pyridine. Pyridine-based materials are valued for their optical and physical properties as well as their medical potential. Additionally, pyridine-based natural products continue to be discovered and studied for their properties and to understand their biosynthesis.Name: 5-Bromo-2-chloropyridine

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

《Endowing 2,6-bis-triazolyl-pyridine of poor extraction with superior efficiency for actinide/lanthanide separation at high acidity by anchoring to a macrocyclic scaffold》 was written by Cai, Yimin; Yan, Qiang; Wang, Mengxin; Chen, Jing; Fu, Haiying; Ye, Jiawei; Conradson, Steven D.; Yuan, Lihua; Xu, Chao; Feng, Wen. Formula: C5H3Br2NThis research focused ontriazolylpyridine macrocyclic scaffold extractant solvent extraction actinide lanthanide separation; Actinide; Lanthanide; N-donor ligand; Separation; Solvent extraction. The article conveys some information:

Exploring nitrogen-containing extractants for recovering hazardous minor actinides that are workable in solutions of high acidity has been a challenge in nuclear waste treatment. Herein, we report our findings that 2,6-bis-triazolyl-pyridine (PyTri), which is ineffective as a hydrophobic ligand for minor actinide separation, turns into an excellent extractant that exhibits unexpectedly high efficiency and selectivity (SFAm/Eu = 172, 1 M HNO3) when attaching to pillar[5]arene platform. Surprisingly, the distribution ratio of Am(III) (DAm) is 4300 times higher than that of the acyclic PyTri ligand. The solvent extraction performance of this pillar[5]arene-achored PyTri not only far exceeds the best known pillar[5]arene ligands reported to date, but also stays comparable to other reported outstanding extractants. Slope anal. indicates that each P[5]A-PyTri can bind two metal ions, which is further corroborated by spectroscopic characterizations. Thermodn. studies imply that the extraction process is exothermic and spontaneous in nature. Complexation investigation via EXAFS technique and DFT calculations strongly suggest that each Eu(III) ion is coordinated to three PyTri arms through a nine-coordination mode. This work provides a N-donor extractant that can operate at high acidity for minor actinide partitioning and implicates a promising approach for transforming poor extractants into superior ones.2,6-Dibromopyridine(cas: 626-05-1Formula: C5H3Br2N) was used in this study.

2,6-Dibromopyridine(cas: 626-05-1) belongs to pyridine. Pyridine-based materials are valued for their optical and physical properties as well as their medical potential. Additionally, pyridine-based natural products continue to be discovered and studied for their properties and to understand their biosynthesis.Formula: C5H3Br2N

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

《Proximity effects in pyridines. Proton chemical shifts in substituted methyl pyridinecarboxylates》 was published in Organic Magnetic Resonance in 1975. These research results belong to Deady, L. W.; Harrison, P. M.; Topsom, R. D.. HPLC of Formula: 29681-39-8 The article mentions the following:

The chem. shifts in 6 series of substituted Me pyridinecarboxylates were measured and interpreted in terms of proximity effects. The shifts for ring H ortho and para to the substituent were explained by additive ester, nitrogen, and substituent effects. The results for meta H indicated substituent-nitrogen interactions, especially when both substituent and H were adjacent N. Similar results were obtained for the ester H. The experimental part of the paper was very detailed, including the reaction process of Methyl 5-methoxypicolinate(cas: 29681-39-8HPLC of Formula: 29681-39-8)

Methyl 5-methoxypicolinate(cas: 29681-39-8) belongs to pyridine. Pyridine-based materials are valued for their optical and physical properties as well as their medical potential. Additionally, pyridine-based natural products continue to be discovered and studied for their properties and to understand their biosynthesis.HPLC of Formula: 29681-39-8

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

《Zinc-Chelating Small Molecules Preferentially Accumulate and Function within Pancreatic β Cells》 was written by Horton, Timothy M.; Allegretti, Paul A.; Lee, Sooyeon; Moeller, Hannah P.; Smith, Mark; Annes, Justin P.. Electric Literature of C12H13N3This research focused onzinc DYRK1A insulin pharmacophore pancreatic beta cell; chelation; diabetes; islet; targeted compound delivery; targeting; tissue selectivity; zinc; β cell; β-cell regeneration; β-cell-replication. The article conveys some information:

Diabetes is a hyperglycemic condition characterized by pancreatic β-cell dysfunction and depletion. Whereas methods for monitoring β-cell function in vivo exist, methods to deliver therapeutics to β cells are lacking. We leveraged the rare ability of β cells to concentrate zinc to preferentially trap zinc-binding mols. within β cells, resulting in β-cell-targeted compound delivery. We determined that zinc-rich β cells and islets preferentially accumulated TSQ (6-methoxy-8-p-toluenesulfonamido-quinoline) in a zinc-dependent manner compared with exocrine pancreas. Next, we asked whether appending a zinc-chelating moiety onto a β-cell replication-inducing compound was sufficient to confer preferential β-cell accumulation and activity. Indeed, the hybrid compound preferentially accumulated within rodent and human islets in a zinc-dependent manner and increased the selectivity of replication-promoting activity toward β cells. These data resolve the fundamental question of whether intracellular accumulation of zinc-chelating compounds is influenced by zinc content. Furthermore, application of this principle yielded a proof-of-concept method for β-cell-targeted drug delivery and bioactivity. The experimental part of the paper was very detailed, including the reaction process of Bis(pyridin-2-ylmethyl)amine(cas: 1539-42-0Electric Literature of C12H13N3)

Bis(pyridin-2-ylmethyl)amine(cas: 1539-42-0) is a secondary amine with two picolyl substituents. The compound is a tridentate ligand in coordination chemistry and commonly used to produce Zn-based chemosensors/probes, such as Zinpry.Electric Literature of C12H13N3

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Category: pyridine-derivativesOn October 20, 2003 ,《Coordination Properties of New Bis(1,4,7-triazacyclononane) Ligands: A Highly Active Dizinc Complex in Phosphate Diester Hydrolysis》 was published in Inorganic Chemistry. The article was written by Arca, Massimiliano; Bencini, Andrea; Berni, Emanuela; Caltagirone, Claudia; Devillanova, Francesco A.; Isaia, Francesco; Garau, Alessandra; Giorgi, Claudia; Lippolis, Vito; Perra, Alessandro; Tei, Lorenzo; Valtancoli, Barbara. The article contains the following contents:

The synthesis and characterization of three new bis([9]aneN3) ligands, containing resp. 2,2′-bipyridine (L1), 1,10-phenanthroline (L2), and quinoxaline (L3) moieties linking the two macrocyclic units, are reported. Proton binding and Cu(II), Zn(II), Cd(II), and Pb(II) coordination with L1-L3 were studied by potentiometric titrations and, for L1 and L2, by spectrophotometric UV-visible measurements in aqueous solutions All ligands can give stable mono- and dinuclear complexes. In the case of L1, trinuclear Cu(II) complexes are also formed. The stability constants and structural features of the formed complexes are strongly affected by the different architecture and binding properties of the spacers bridging the two [9]aneN3 units. In the case of the L1 and L2 mononuclear complexes, the metal is coordinated by the three donors of one [9]aneN3 moiety; in the [ML2]2+ complexes, however, the phenanthroline nitrogens are also involved in metal binding. Finally, in the [ML3]2+ complexes both macrocyclic units, at a short distance from each other, can be involved in metal coordination, giving rise to sandwich complexes. In the binuclear complexes each metal ion is generally coordinated by one [9]aneN3 unit. In L1, however, the dipyridine nitrogens can also act as a potential binding site for metals. The dinuclear complexes show a marked tendency to form mono-, di-, and, in some cases, trihydroxo species in aqueous solutions The resulting M-OH functions may behave as nucleophiles in hydrolytic reactions. The hydrolysis rate of bis(p-nitrophenyl)phosphate (BNPP) was measured in aqueous solution at 308.1 K in the presence of the L2 and L3 dinuclear Zn(II) complexes. Both the L2 complexes [Zn2L2(OH)2]2+ and [Zn2L2(OH)3]+ and the L3 complex [Zn2L3(OH)3]+ promote BNPP hydrolysis. The [Zn2L3(OH)3]+ complex is ∼2 orders of magnitude more active than the L2 complexes, due both to the short distance between the metal centers in [Zn2L3(OH)3]+, which could allow a bridging interaction of the phosphate ester, and to the simultaneous presence of single-metal bound nucleophilic Zn-OH functions. These structural features are substantially corroborated by semiempirical PM3 calculations carried out on the mono-, di-, and trihydroxo species of the L3 dizinc complex. In addition to this study using 4,4′-Bis(chloromethyl)-2,2′-bipyridine, there are many other studies that have used 4,4′-Bis(chloromethyl)-2,2′-bipyridine(cas: 138219-98-4Category: pyridine-derivatives) was used in this study.

4,4′-Bis(chloromethyl)-2,2′-bipyridine(cas: 138219-98-4) belongs to pyridine derivatives. Several pyridine derivatives play important roles in biological systems. While its biosynthesis is not fully understood, nicotinic acid (vitamin B3) occurs in some bacteria, fungi, and mammals. Category: pyridine-derivatives

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Bakke, Jan M.; Ranes, Eli; Riha, Jaroslav; Svensen, Harald published an article on February 28 ,1999. The article was titled 《The synthesis of β-nitropyridine compounds》, and you may find the article in Acta Chemica Scandinavica.HPLC of Formula: 59290-82-3 The information in the text is summarized as follows:

Pyridine and a number of substituted pyridines have been nitrated by reaction with N2O5 followed by reaction with an aqueous solution of SO2xH2O or NaHSO3. The dependence of the yields on the pH of the aqueous reaction medium, on the concentration of SO2xH2O-HSO3-, on addition of methanol to the aqueous phase, and on the reaction temperature were investigated. The yields obtained with NaHSO3 were: 3-nitropyridine 77%, 2-methyl-5-nitropyridine 36%, 3-methyl-5-nitropyridine 24%, 3-acetyl-5-nitropyridine 18%, 5-nitropyridine-3-carboxylic acid 15%, 3-chloro-5-nitropyridine 11%, 4-methyl-3-nitropyridine 39%, 4-acetyl-3-nitropyridine 67%, 4-cyano-3-nitropyridine 45%, 4-phenyl-3-nitropyridine 68%, 4-formyl-3-nitropyridine 62% (from reaction in liquid SO2), 3-nitropyridine-4-carboxylic acid 48%, Me 3-nitropyridine-4-carboxylate 75%, 2,3-dimethyl-5-nitropyridine 37%, 2,4-dimethyl-5-nitropyridine 64%, 3-nitroquinoline 10% and 4-nitroisoquinoline 42%. The experimental part of the paper was very detailed, including the reaction process of 3-Nitroisonicotinic acid(cas: 59290-82-3HPLC of Formula: 59290-82-3)

3-Nitroisonicotinic acid(cas: 59290-82-3) belongs to pyridine. Pyridine, its benzo and pyridine-based compounds play diverse roles in organic chemistry. As ligands, solvents, and catalysts they facilitate reactions; thus descriptions of these new ligands and their applications abound each year.HPLC of Formula: 59290-82-3

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Chatterjee, Tanmay; Sarma, Monima; Das, Samar K. published their research in Tetrahedron Letters on December 29 ,2010. The article was titled 《Donor-acceptor amphiphilic 2,2′-bipyridine chromophores: synthesis, linear optical, and thermal properties》.Related Products of 138219-98-4 The article contains the following contents:

Two sym. and one unsym. push-pull amphiphilic 2,2′-bipyridine chromophores were synthesized through Horner-Wadsworth-Emmons and Knoevenagel reaction mechanized synthetic protocols and characterized by spectroscopy. The linear optical properties and thermal stability of the synthesized chromophores were studied. In the experiment, the researchers used 4,4′-Bis(chloromethyl)-2,2′-bipyridine(cas: 138219-98-4Related Products of 138219-98-4)

4,4′-Bis(chloromethyl)-2,2′-bipyridine(cas: 138219-98-4) belongs to pyridine derivatives. Several pyridine derivatives play important roles in biological systems. While its biosynthesis is not fully understood, nicotinic acid (vitamin B3) occurs in some bacteria, fungi, and mammals. Related Products of 138219-98-4

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

In 2017,Chen, Fu-Min; Huang, Fei-Dong; Yao, Xue-Yi; Li, Tian; Liu, Feng-Shou published 《Direct C-H heteroarylation by an acenaphthyl-based α-diimine palladium complex: improvement of the reaction efficiency for bi(hetero)aryls under aerobic conditions》.Organic Chemistry Frontiers published the findings.Reference of 5-Bromo-2-chloropyridine The information in the text is summarized as follows:

A bulky acenaphthyl skeleton-based α-diimine palladium complex with ortho-tert-Bu on N-aryl moieties was designed, synthesized and characterized. The developed palladium complex was applied for direct C-H arylation under aerobic reaction conditions. A range of heteroaryls, such as thiazoles, thiophenes, furans, imidazopyridines, indolizines, isoxazoles, imidazoles, triazoles, pyrazoles, indoles, pyrroles and pyrazolidinones, were used, while various coupling partners of heteroaryl bromides with wide functional groups were compatible. Upon using 0.05-0.1 mol% of a precatalyst, more than 90 examples of cross-coupling products were afforded in good to excellent yields, demonstrating that this phosphine-free catalytic system scaffold enables a general access to biheteroaryls. After reading the article, we found that the author used 5-Bromo-2-chloropyridine(cas: 53939-30-3Reference of 5-Bromo-2-chloropyridine)

5-Bromo-2-chloropyridine(cas: 53939-30-3) belongs to pyridine. Pyridine is very deactivated towards electrophilic substitution with respect to benzene. For this reason classical formylation, using methods such as the Gattermann or Vilsmeier reactions, are not generally successful. Reference of 5-Bromo-2-chloropyridine

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

In 2018,Kirlikovali, Kent O.; Cho, Eunho; Downard, Tyler J.; Grigoryan, Lilit; Han, Zheng; Hong, Sooji; Jung, Dahee; Quintana, Jason C.; Reynoso, Vanessa; Ro, Sooihk; Shen, Yi; Swartz, Kevin; Ter Sahakyan, Elizabeth; Wixtrom, Alex I.; Yoshida, Brandon; Rheingold, Arnold L.; Spokoyny, Alexander M. published 《Buchwald-Hartwig amination using Pd(I) dimer precatalysts supported by biaryl phosphine ligands》.Dalton Transactions published the findings.Related Products of 53939-30-3 The information in the text is summarized as follows:

The synthesis of air-stable Pd(I) dimer complexes featuring biaryl phosphine ligands was reported. Catalytic experiments suggested that these complexes were competent precatalysts that mediated cross-coupling amination reaction between aryl halides with both aliphatic and aromatic amine nucleophiles. An expansion of the air-stable precatalyst toolbox for Pd-catalyzed cross-coupling transformations were represented. The results came from multiple reactions, including the reaction of 5-Bromo-2-chloropyridine(cas: 53939-30-3Related Products of 53939-30-3)

5-Bromo-2-chloropyridine(cas: 53939-30-3) belongs to pyridine. Pyridine is widely used in the precursor to agrochemicals and pharmaceuticals. Also, it is used as an important reagent and organic solvent.Related Products of 53939-30-3

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem