Day: February 9, 2023

How multiple noncovalent interactions regulate the aggregation behavior of amphiphilic triblock copolymer/surface-active ionic liquid mixtures was written by Luo, Haiyan;Jiang, Kun;Wang, Xiaotian;Yao, Haoyu;Liang, Xiangfeng;Li, Yingbo;Liu, Huizhou. And the article was included in Journal of Molecular Liquids in 2022.HPLC of Formula: 104-73-4 This article mentions the following:

Amphiphilic block copolymers/ionic liquids mixtures have been emerging as a new class of ‘chem. entity’ with numerous advanced applications. However, interaction mechanism governing the aggregation and the microstructure of aggregates are still far from full understanding. Herein, the role of noncovalent interactions in regulation of aggregation behaviors of mixtures of Pluronic F127 and surface-active ionic liquids, i.e. C_nmimBr, C_nPyBr and C_nMPB is investigated by DLS, cryo-TEM, NMR and mol. dynamics simulation. The interaction modes between F127 and SAILs are remarkably dependent on the concentration and cationic headgroup of SAIL. At low SAIL concentration (<CMC), mixed micelles mainly composed of F127 with some SAIL cations embedded into micelles are formed, which was primarily driven by hydrophobic interaction. However, the residence of C_nmimBr cations in micelles is quite different from that of C_nPyBr and C_nMPB cations due to its distinctive hydrogen bonding with PEO segment of F127. Upon further addition of SAILs (CSAILs > CMC), gradual disintegration of F127-rich micelles was observed due to the enhanced repulsive electrostatic force at micellar core-corona interface, accompanying with the re-formation of two types of micelles: one consisting of pure SAILs and one that SAIL micelles bound with F127 monomers via hydrogen bonding and/or hydrophobic interactions. This work provides new insight into the aggregation mechanism of these complex systems and will be helpful to rational tailoring innovative copolymers /IL-based system for specific applications. In the experiment, the researchers used many compounds, for example, 1-Dodecylpyridin-1-ium bromide (cas: 104-73-4HPLC of Formula: 104-73-4).

1-Dodecylpyridin-1-ium bromide (cas: 104-73-4) belongs to pyridine derivatives. The ring atoms in the pyridine molecule are sp2-hybridized. The nitrogen is involved in the π-bonding aromatic system using its unhybridized p orbital. The lone pair is in an sp2 orbital, projecting outward from the ring in the same plane as the σ bonds. One of the examples of pyridines is the well-known alkaloid lithoprimidine, which is an A3 adenosine receptor antagonist and N,N-dimethylaminopyridine (DMAP) analog, commonly used in organic synthesis.HPLC of Formula: 104-73-4

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Novel fleximer pyrazole-containing adenosine analogues: chemical, enzymatic and highly efficient biotechnological synthesis was written by Khandazhinskaya, Anastasia;Eletskaya, Barbara;Fateev, Ilja;Kharitonova, Maria;Konstantinova, Irina;Barai, Vladimir;Azhayev, Alex;Hyvonen, Mervi T.;Keinanen, Tuomo A.;Kochetkov, Sergey;Seley-Radtke, Katherine;Khomutov, Alex;Matyugina, Elena. And the article was included in Organic & Biomolecular Chemistry in 2021.Computed Properties of C10H13BrN2O2 This article mentions the following:

Nucleoside analogs have long served as key chemotherapeutic drugs for the treatment of viral infections and cancers. Problems associated with the development of drug resistance have led to a search for the design of nucleosides capable of bypassing point mutations in the target enzyme’s binding site. As a possible answer to this, the Seley-Radtke group developed a flexible nucleoside scaffold (fleximers), where the heterocyclic purine base is split into its two components, i.e. pyrimidine and imidazole. Herein, we present a series of new pyrazole-containing flex-bases and the corresponding fleximer analogs of 8-aza-7-deaza nucleosides. Subsequent studies found that pyrazole-containing flex-bases are substrates of purine nucleoside phosphorylase (PNP). We have compared the chem. synthesis of fleximers and enzymic approaches with both isolated enzymes and the use of E. coli cells over-producing PNP. The latter provided stereochem. pure pyrazole-containing β-D-ribo- and β-D-2′-deoxyribo-fleximers and are beneficial in terms of environmental issues, are more economical, and streamline the steps required from a chem. approach. The reaction is carried out in water, avoiding hazardous chems., and the products are isolated by ion-exchange chromatog. using water/ethanol mixtures for elution. Moreover, the target nucleosides were obtained on a multi-milligram scale with >97-99% purity, and the reactions can be easily scaled up. In the experiment, the researchers used many compounds, for example, tert-Butyl (3-bromopyridin-4-yl)carbamate (cas: 257937-08-9Computed Properties of C10H13BrN2O2).

tert-Butyl (3-bromopyridin-4-yl)carbamate (cas: 257937-08-9) belongs to pyridine derivatives. Pyridine is diamagnetic and has a diamagnetic susceptibility of −48.7 × 10−6 cm3·mol−1.The molecular electric dipole moment is 2.2 debyes. The standard enthalpy of formation is 100.2 kJ·mol−1 in the liquid phase and 140.4 kJ·mol−1 in the gas phase. 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.Computed Properties of C10H13BrN2O2

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Asymmetric Transfer Hydrogenative Amination of Benzylic Ketones Catalyzed by Cp*Ir(III) Complexes Bearing a Chiral N-(2-Picolyl)sulfonamidato Ligand was written by Kawada, Takuma;Yabushita, Kenya;Yasuda, Toshihisa;Ohta, Takeshi;Yajima, Takaaki;Tanaka, Kouichi;Utsumi, Noriyuki;Watanabe, Masahito;Murata, Kunihiko;Kayaki, Yoshihito;Kuwata, Shigeki;Katayama, Takeaki. And the article was included in Journal of Organic Chemistry in 2022.Name: Phenyl(pyridin-2-yl)methanone This article mentions the following:

A convenient asym. reductive amination of benzylic ketones (α-arylated ketones) catalyzed by newly designed Cp*Ir complexes bearing a chiral N-(2-picolyl)sulfonamidato ligand was developed. Using readily available β-amino alcs. as chiral aminating agents, a range of benzo-fused and acyclic ketones were successfully reduced with formic acid in methanol at 40°C to afford amines with favorable chemo- and diastereoselectivities. The amino alc.-derived chiral auxiliary was easily removed by mild periodic oxidants, leading to optically active primary β-arylamines without erosion of the optical purity (up to 97% ee). The excellent catalytic performance was retained even upon lowering the amount of catalyst to a substrate/catalyst (S/C) ratio of 20,000, and the amination could be performed on a large scale exceeding 100 g. The precise hydride transfer to iminium species generated from the ketonic substrate and the chiral amine counterpart was suggested by the mechanistic studies on stoichiometric reactions of isolable hydridoiridium complexes and model intermediates such as N,O-acetal, enamine, and iminium compounds In the experiment, the researchers used many compounds, for example, Phenyl(pyridin-2-yl)methanone (cas: 91-02-1Name: Phenyl(pyridin-2-yl)methanone).

Phenyl(pyridin-2-yl)methanone (cas: 91-02-1) belongs to pyridine derivatives. The pyridine ring occurs in many important compounds, including agrochemicals, pharmaceuticals, and vitamins. One of the examples of pyridines is the well-known alkaloid lithoprimidine, which is an A3 adenosine receptor antagonist and N,N-dimethylaminopyridine (DMAP) analog, commonly used in organic synthesis.Name: Phenyl(pyridin-2-yl)methanone

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Understanding the role of Dimethylformamide as co-solvents in the dissolution of cellulose in ionic liquids: Experimental and theoretical approach was written by Phadagi, R.;Singh, S.;Hashemi, H.;Kaya, S.;Venkatesu, P.;Ramjugernath, D.;Ebenso, E. E.;Bahadur, I.. And the article was included in Journal of Molecular Liquids in 2021.Quality Control of 1-Butyl-3-methylpyridinium Chloride This article mentions the following:

Cellulose has been identified as the most abundant renewable material but however utilization of cellulose is still limited, it does not dissolve in most convectional solvents. This study focusses on cellulose dissolution using ionic liquids namely: 1-butyl-3-methylimidazolium chloride ([BMIM][Cl]), 1-allyl-3-methylimidazolium chloride ([AMIM][Cl]) and 1-butyl-3-methylpyridinium chloride ([BMPy][Cl]) with N, N-dimethylformamide co-solvent. The solubility of the cellulose was tested in pure ILs as well as in solution of ILs/DMF. Results showed that solubility of the cellulose in ILs greatly enhanced in the presence of DMF. The complete dissolution of cellulose in both the systems such as pure ILs and ILs/DMF was also evident by d. (ρ), sound velocity (μ) and refractive index (n_D) measurements. Furthermore, COSMO-RS anal. was also performed in order to achieve a better understanding of the mol. interactions between the ILs and the co-solvent. In addition to the above theor. chem. tools, natural bond orbital (NBO), fragment MO (FMO) and chem. reactivity analyzes for cellulose mol. was investigated. Theor. data obtained proved that cellulose mol. is more reactive than glucose. In addition, this study also deals with the regeneration of the cellulose from dissolved solution using deionized water. The regenerated cellulose was characterized by fourier transform IR spectroscopy, X-ray diffraction, SEM, thermogravimetric anal. and differential scanning calorimetry techniques. It was observed that the cellulose regenerated cellulose from both solvent systems hold excellent mech. properties. In the experiment, the researchers used many compounds, for example, 1-Butyl-3-methylpyridinium Chloride (cas: 125652-55-3Quality Control of 1-Butyl-3-methylpyridinium Chloride).

1-Butyl-3-methylpyridinium Chloride (cas: 125652-55-3) belongs to pyridine derivatives. The pyridine ring occurs in many important compounds, including agrochemicals, pharmaceuticals, and vitamins. Pyridine derivatives are also useful as small-molecule α-helix mimetics that inhibit protein-protein interactions, as well as functionally selective GABA ligands.Quality Control of 1-Butyl-3-methylpyridinium Chloride

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Light-promoted synthesis of surface-grafted polymers bearing pyridine groups by metal-free ATRP in microliter volumes was written by Slowikowska, Monika;Wojcik, Artur J.;Wolski, Karol;Hatalak, Anna;Zapotoczny, Szczepan. And the article was included in Polymer in 2021.Synthetic Route of C5H5NO This article mentions the following:

Polymers with pendant pyridine groups (PPPGs) are pH responsive weak polyelectrolytes potentially attractive for many applications such as sensors, antibacterial coatings, and ion gating systems. Synthesis of PPPGs by classical atom transfer radical polymerization (ATRP) is challenging due to highly probable formation of monomer/metal complexes. In response to that, we report here a facile synthetic strategy to obtain surface-grafted PPPGs that utilizes light-mediated ATRP. Metal-free surface-initiated ATRP catalyzed by 10-phenylphenothiazine is used to polymerize three isomeric monomers with methacrylate groups attached at various positions of a pyridine ring. The reactivity of the isomers is compared for selection of optimal monomer structure leading to thick brushes. The polymerizations are conducted under visible light, at ambient conditions, and using only microliter volumes of the reaction mixture that is important for reducing the complexity and costs of the process and limiting chem. waste. The observed linear dependency of the brush thickness vs. polymerization time for poly(pyridin-3-yl methacrylate) (PP3M) grafted from indium tin oxide or silicon wafers indicated the controlled characteristics of the developed method. The obtained PP3M brush demonstrated pH responsive behavior associated with protonation of pyridine groups in acidic solution and adoption of highly stretched conformation below pK_a. In the experiment, the researchers used many compounds, for example, Pyridin-4-ol (cas: 626-64-2Synthetic Route of C5H5NO).

Pyridin-4-ol (cas: 626-64-2) belongs to pyridine derivatives. The pyridine ring occurs in many important compounds, including agrochemicals, pharmaceuticals, and vitamins. Pyridine, its benzo and pyridine-based compounds play diverse roles in organic chemistry. Pyridine-based materials are valued for their optical and physical properties as well as their medical potential. Synthetic Route of C5H5NO

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Kinetics and mechanism of bromination of 2-pyridinone and related derivatives in aqueous solution was written by Tee, Oswald S.;Paventi, Martino. And the article was included in Journal of the American Chemical Society in 1982.Electric Literature of C5H3Br2NO This article mentions the following:

The tautomeric system 2-pyridone (I) ⇄ 2-hydroxypyridine (II) reacts with aqueous Br via the principal tautomer I at pH <6 and via the conjugate anion at pH >6. Attack upon I occurs preferentially at the 3 position, whereas reaction of the anion probably involves major attack at the 5 position. The facile dibromination of I results from the comparable reactivity of the monobromopyridones at pH <1 or pH >4. These conclusions are based upon kinetic and product studies of I bromination and various derivatives in aqueous solutions at pH 0-8. With respect to their reactivity toward Br, the pyridones behave as substituted phenoxide ions. In the experiment, the researchers used many compounds, for example, 3,5-Dibromo-2-hydroxypyridine (cas: 13472-81-6Electric Literature of C5H3Br2NO).

3,5-Dibromo-2-hydroxypyridine (cas: 13472-81-6) belongs to pyridine derivatives. Pyridine has a conjugated system of six π electrons that are delocalized over the ring. The molecule is planar and, thus, follows the Hückel criteria for aromatic systems. One of the examples of pyridines is the well-known alkaloid lithoprimidine, which is an A3 adenosine receptor antagonist and N,N-dimethylaminopyridine (DMAP) analog, commonly used in organic synthesis.Electric Literature of C5H3Br2NO

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Cytotoxicity estimation of ionic liquids based on their effective structural features was written by Fatemi, Mohammad H.;Izadiyan, Parisa. And the article was included in Chemosphere in 2011.Application of 125652-55-3 This article mentions the following:

Cytotoxicity of a diverse set of 227 ionic liquids (taken from UFT/Merck Ionic Liquids Biol. Effects Database) containing 94 imidazolium, 53 pyridinium, 23 pyrrolidinium, 22 ammonium, 15 piperidinium, 10 morpholinium, 5 phosphanium, and 5 quinolinium cations in combination with 25 different types of anions to Leukemia Rat Cell Line (IPC-81) was estimated from their structural parameters using quant. structure – toxicity relationship “QSTR” methodol. Linear and nonlinear models were developed using genetic algorithm (GA), multiple linear regressions (MLR) and multilayer perceptron neural network (MLP NN) approaches. Robustness and reliability of the constructed models were evaluated through internal and external validation methods. Furthermore, chem. applicability domain was determined via leverage approach. In this work, it was revealed that the cationic moieties make the major contribution to cytotoxicity and the anionic parts play a secondary role in cytotoxicity of the ionic liquids studied here. Structural information represented in this work, can be used for a rational design of safer ILs. In the experiment, the researchers used many compounds, for example, 1-Butyl-3-methylpyridinium Chloride (cas: 125652-55-3Application of 125652-55-3).

1-Butyl-3-methylpyridinium Chloride (cas: 125652-55-3) belongs to pyridine derivatives. Pyridine is diamagnetic and has a diamagnetic susceptibility of −48.7 × 10−6 cm3·mol−1.The molecular electric dipole moment is 2.2 debyes. The standard enthalpy of formation is 100.2 kJ·mol−1 in the liquid phase and 140.4 kJ·mol−1 in the gas phase. Many analogues of pyridine are known where N is replaced by other heteroatoms . Substitution of one C–H in pyridine with a second N gives rise to the diazine heterocycles (C4H4N2), with the names pyridazine, pyrimidine, and pyrazine.Application of 125652-55-3

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Protonation Studies of Molybdenum(VI) Nitride Complexes That Contain the [2,6-(ArNCH₂)₂NC₅H₃]^2- Ligand (Ar = 2,6-Diisopropylphenyl) was written by Hickey, Anne K.;Wickramasinghe, Lasantha A.;Schrock, Richard R.;Tsay, Charlene;Muller, Peter. And the article was included in Inorganic Chemistry in 2019.Safety of Pyridinehydrochloride This article mentions the following:

[Ar₂N₃]Mo(N)(O-t-Bu) (1), which contains the conformationally rigid pyridine-based diamido ligand [2,6-(ArNCH₂)₂NC₅H₃]^2- (Ar = 2,6-diisopropylphenyl), is a catalyst for the reduction of dinitrogen with protons and electrons. Various acids have been added in order to explore where and how the first proton adds to the complex. The addition of adamantol to 1 produces a five-coordinate bis(adamantoxide), [HAr₂N₃]Mo(N)(OAd)₂ (2a), in which one of the amido nitrogens in the ligand has been protonated and the resulting aniline nitrogen in the [HAr₂N₃]^– ligand is not bound to the metal. The addition of [Ph₂NH₂][OTf] to 1 produces {[HAr₂N₃]Mo(N)(O-t-Bu)}(OTf) (3), in which an amido nitrogen has been protonated, but the aniline in the [HAr₂N₃]^– ligand remains bound to the metal. Last, the addition of (2,6-lutidinium)BAr^F₄ (BAr^F₄ = {B(3,5-(CF₃)₂C₆H₃)₄}^–) to 1 yields {[Ar₂N₃]Mo(N)(LutH)(O-t-Bu)}BAr^F₄, in which LutH⁺ is hydrogen-bonded to the nitride in the solid state and in dichloromethane with K_eq = 412 ± 94 and ΔG = -3.6 ± 0.8 kcal at 22 °C. A similar hydrogen-bonded adduct was formed through the addition of (2-methylpyridinium)BAr^F₄ to 1, but the addition of (pyridinium)BAr^F₄ to 1 leads to the formation of (inter alia) {[HAr₂N₃]Mo(N)(O-t-Bu)}(BAr^F₄), in which the amide nitrogen has been protonated. The addition of cobaltocene to 3 or {[Ar₂N₃]Mo(N)(LutH)(O-t-Bu)}(BAr^F₄) leads only to the re-formation of 1. X-ray structural studies were carried out on 2a, 3, and {[Ar₂N₃]Mo(N)(LutH)(O-t-Bu)}(BAr^F₄). In the experiment, the researchers used many compounds, for example, Pyridinehydrochloride (cas: 628-13-7Safety of Pyridinehydrochloride).

Pyridinehydrochloride (cas: 628-13-7) belongs to pyridine derivatives. In contrast to benzene, Pyridine’s electron density is not evenly distributed over the ring, reflecting the negative inductive effect of the nitrogen atom. Many analogues of pyridine are known where N is replaced by other heteroatoms . Substitution of one C–H in pyridine with a second N gives rise to the diazine heterocycles (C4H4N2), with the names pyridazine, pyrimidine, and pyrazine.Safety of Pyridinehydrochloride

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Ring transformations in reactions of heterocyclic halo compounds with nucleophiles. XII. Action of potassium amide on 2-bromo-and 2,6-dibromo-3-hydroxypyridine was written by Roelfsema, W. A.;Den Hertog, H. J.. And the article was included in Tetrahedron Letters in 1967.Product Details of 6602-33-1 This article mentions the following:

2-Bromo-3-hydroxypyridine (I) was prepared from 3-ethoxy-2-nitropyridine. I treated 2 hrs. at -33° with an 8-fold molar amount of KNH2 in liquid NH3 yielded 85% pyrrole-2-carboxamide (II), m. 172.5-4.0°, also synthesized from pyrrole-2-carboxylic acid. Similarly 2,6-dibromo-3-hydroxypyridine, prepared from 3-hydroxypyridine, was converted to 80% 5-bromopyrrole-2-carboxamide, m. 136-8°. Apparently the conversion occurs without bond fission between C-2 and C-3 as in the analogous transformations of 3-amino-2-bromopyridine and 3-amino-2-bromoquinoline, but that the pyridine rings are broken between C-3 and C-4 atoms. A tentative reaction scheme for the conversion is given. In the experiment, the researchers used many compounds, for example, 2,6-Dibromo-3-hydroxypyridine (cas: 6602-33-1Product Details of 6602-33-1).

2,6-Dibromo-3-hydroxypyridine (cas: 6602-33-1) belongs to pyridine derivatives. Pyridines are an important class of heterocycles and occur in polysubstituted forms in many naturally occurring biologically active compounds, drug molecules and chiral ligands. Halopyridines are particularly attractive synthetic building blocks in a variety of cross-coupling methods, including the Suzuki-Miyaura cross-coupling reaction.Product Details of 6602-33-1

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Sulfur(IV)-Mediated Unsymmetrical Heterocycle Cross-Couplings was written by Zhou, Min;Tsien, Jet;Qin, Tian. And the article was included in Angewandte Chemie, International Edition in 2020.Synthetic Route of C8H11N This article mentions the following:

Despite the tremendous utilities of metal-mediated cross-couplings in modern organic chem., coupling reactions involving nitrogenous heteroarenes remain a challenging undertaking – coordination of Lewis basic atoms into metal centers often necessitate elevated temperature, high catalyst loading, etc. Herein, the authors report a sulfur (IV) mediated cross-coupling amendable for the efficient synthesis of heteroaromatic substrates. Addition of heteroaryl nucleophiles to a simple, readily-accessible alkyl sulfinyl (IV) chloride gave a trigonal bipyramidal sulfurane intermediate. Reductive elimination therefrom provides bis-heteroaryl products in a practical and efficient fashion. In the experiment, the researchers used many compounds, for example, 2-Isopropylpyridine (cas: 644-98-4Synthetic Route of C8H11N).

2-Isopropylpyridine (cas: 644-98-4) belongs to pyridine derivatives. Pyridine’s the lone pair does not contribute to the aromatic system but importantly influences the chemical properties of pyridine, as it easily supports bond formation via an electrophilic attack. Reduced pyridines, namely tetrahydropyridines, dihydropyridines and piperidines, are found in numerous natural and synthetic compounds. The synthesis and reactivity of these compounds have often been driven by the fact many of these compounds have interesting and unique pharmacological properties. Synthetic Route of C8H11N

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem