Month: February 2023

Spectral and ionization constant studies of substituted 2-hydroxypyridines(1,2-dihydro-2-oxopyridines) was written by Spinner, E.;White, J. C. B.. And the article was included in Journal of the Chemical Society [Section] B: Physical Organic in 1966.HPLC of Formula: 13472-81-6 This article mentions the following:

The uv and ir spectra and the ionization constants of the title compounds containing substituents (3-, 4-, 5-, and 6-Me; 3- and 5-Cl; 3,5-Cl₂; 3- and 5-Br; 3,5-Br₂; 5-I; 3,5-I₂; 3- and 6-OH; 3- and 6-O^–; 3- and 5-NO₂) have been determined For all the compounds examined the pyridone form predominates. A number of the corresponding 2-methoxypyridines were also studied for reference. 34 references. In the experiment, the researchers used many compounds, for example, 3,5-Dibromo-2-hydroxypyridine (cas: 13472-81-6HPLC of Formula: 13472-81-6).

3,5-Dibromo-2-hydroxypyridine (cas: 13472-81-6) 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. 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: 13472-81-6

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Synthesis of 5-amino or 4-amino substituted 7-aza-isoindolin-1-ones was written by Zhou, Heng;Shi, Qunfeng;Liu, Xiangchao;Zhan, Xiaoping;Liu, Zenglu;Mao, Zhenmin. And the article was included in Heterocycles in 2013.Category: pyridine-derivatives This article mentions the following:

A simple and convenient route for the synthesis of a series of 5- and 4-amino-7-azaisoindolin-1-ones is described. Me amino-3-(bromomethyl)picolinates were cyclized with different amines under alk. conditions to give the desired products. In the experiment, the researchers used many compounds, for example, Methyl 3-methylpicolinate (cas: 59718-84-2Category: pyridine-derivatives).

Methyl 3-methylpicolinate (cas: 59718-84-2) belongs to pyridine derivatives. The pyridine ring occurs in many important compounds, including agrochemicals, pharmaceuticals, and vitamins. 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. Category: pyridine-derivatives

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Synthesis, optical and theoretical characterization of heteroleptic Iridium(III) Imidazo[1,5-a]pyridine and -quinoline complexes was written by Herr, Jasmin Martha;Roessiger, Carina;Locke, Harald;Wilhelm, Mikko;Becker, Jonathan;Heimbrodt, Wolfram;Schlettwein, Derck;Goettlich, Richard. And the article was included in Dyes and Pigments in 2020.Recommanded Product: Phenyl(pyridin-2-yl)methanone This article mentions the following:

Blue OLEDs are still a challenge of today’s photoelectrochem. The third generation of OLEDs is based on thermally activated delayed fluorescence (TADF). A series of heteroleptic iridium(III) imidazo[1,5-a]pyridine and -quinoline complexes with potential TADF behavior was synthesized and characterized via UV-Vis absorption and fluorescence spectroscopy as well as measurements of the excited state lifetime. The exptl. results were confirmed by computational calculations of the relative energy of the first excited singlet and triplet states. In addition, the HOMO and LUMO levels were calculated with DFT and compared to values estimated from redox potentials determined by cyclic voltammetry. For the first time, a TADF mechanism of these compounds has been proven. In the experiment, the researchers used many compounds, for example, Phenyl(pyridin-2-yl)methanone (cas: 91-02-1Recommanded Product: Phenyl(pyridin-2-yl)methanone).

Phenyl(pyridin-2-yl)methanone (cas: 91-02-1) belongs to pyridine derivatives. Pyridine has a conjugated system of six 闂?electrons that are delocalized over the ring. The molecule is planar and, thus, follows the H闂佹椿浜滈妴鍗l criteria for aromatic systems. 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. Recommanded Product: Phenyl(pyridin-2-yl)methanone

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Biorefining of pigeon pea: residue conversion by pyrolysis was written by Tanquilut, Mari Rowena C.;Genuino, Homer C.;Wilbers, Erwin;Amongo, RossanaMarie C.;Suministrado, Delfin C.;Yaptenco, Kevin F.;Elauria, Marilyn M.;Elauria, Jessie C.;Heeres, Hero J.. And the article was included in Energies (Basel, Switzerland) in 2020.Related Products of 28020-37-3 This article mentions the following:

Pyrolysis is an important technol. to convert lignocellulosic biomass to a renewable liquid energy carrier known as pyrolysis oil or bio-oil. Herein we report the pyrolysis of pigeon pea wood, a widely available biomass in the Philippines, in a semi-continuous reactor at gram scale. The effects of process conditions such as temperature (400-600 闂佺娅ｉ悡?, nitrogen flow rate (7-15 mL min^-1) and particle size of the biomass feed (0.5-1.3 mm) on the product yields were determined A Box-Behnken three-level, three-factor fractional factorial design was carried out to establish process-product yield relations. Of particular interest is the liquid product (bio-oil), of which the yield was shown to depend on all independent variables in a complex manner. The optimal conditions for highest bio-oil yield (54 weight% on dry feed intake) were a temperature of 466 闂佺娅ｉ悡? a nitrogen flow rate of 14 mL min^-1 and a particle size of 1.3 mm. Validation of the optimized conditions proved that the average (n = 3) exptl. bio-oil yield (52 weight%) is in good agreement with the predicted value from the model. The properties of product oils were determined using various anal. techniques including gas chromatog.-mass spectrometry (GC-MS), gel-permeation chromatog. (GPC), NMR spectroscopy (13C- and HSQC-NMR) and elemental and proximate analyses. The bio-oils were shown to have low ash content (0.2%), high heating value (29 MJ kg^-1) and contain high value-added phenolics compounds (41%, GC peak area) as well as low mol. weight aldehydes and carboxylic acids. GPC anal. indicated the presence of a considerable amount of higher mol. weight compounds NMR measurements showed that a large proportion of bio-oil contains aliphatic carbons (~60%), likely formed from the decomposition of (hemi)cellulose components, which are abundantly present in the starting pigeon pea wood. Subsequent preliminary scale-up pyrolysis experiments in a fluidized bed reactor (~100 gfeed h-1, 475 闂佺娅ｉ悡?and N2 flow rate of 1.5 L min^-1) gave a non-optimized bio-oil yield of 44 weight%. Further fractionation and/or processing are required to upgrade these bio-oils to biofuels and biobased chems. In the experiment, the researchers used many compounds, for example, 3-Amino-2,6-dimethoxypyridine (cas: 28020-37-3Related Products of 28020-37-3).

3-Amino-2,6-dimethoxypyridine (cas: 28020-37-3) belongs to pyridine derivatives. The pyridine ring occurs in many important compounds, including agrochemicals, pharmaceuticals, and vitamins. Halopyridines are particularly attractive synthetic building blocks in a variety of cross-coupling methods, including the Suzuki-Miyaura cross-coupling reaction.Related Products of 28020-37-3

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Ionic liquids: predictions of physicochemical properties with experimental and/or DFT-calculated LFER parameters to understand molecular interactions in solution was written by Cho, Chul-Woong;Preiss, Ulrich;Jungnickel, Christian;Stolte, Stefan;Arning, Juergen;Ranke, Johannes;Klamt, Andreas;Krossing, Ingo;Thoeming, Jorg. And the article was included in Journal of Physical Chemistry B in 2011.Application of 125652-55-3 This article mentions the following:

We present evolutionary models to predict the octanol-water partition coefficients (log P), water solubilities, and critical micelle concentrations (CMCs) of ionic liquids (ILs), as well as the anionic activity coefficients and hydrophobicities in pure water and octanol-water. They are based on a polyparameter linear free energy relationship (LFER) using measured and/or DFT-calculated LFER parameters: hydrogen-bonding acidity (A), hydrogen-bonding basicity (B), polarizability/dipolarity (S), excess molar refraction (E), and McGowan volume (V) of IL ions. With both calculated or exptl. LFER descriptors of IL ions, the physicochem. parameters were predicted with an errors of 0.182-0.217 for the octanol-water partition coefficient and 0.131-0.166 logarithmic units for the water solubility Because exptl. determined solute parameters of anions are not currently available, the CMC, anionic activity coefficient, and hydrophobicity were predicted with quantum-chem. methods with R² values of at least 0.99, as well as errors below 0.168 logarithmic units. These new approaches will facilitate the assessment of the tech. applicability and environmental fate of ionic compounds even before their synthesis. 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’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. Application of 125652-55-3

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Corrosion inhibitors. Part II: Quantum chemical studies on the corrosion inhibition of steel in acidic medium by some triazole, oxadiazole and thiadiazole derivatives was written by El Ashry, El Sayed H.;El Nemr, Ahmed;Esawy, Sami A.;Ragab, Safaa. And the article was included in Electrochimica Acta in 2006.SDS of cas: 15420-02-7 This article mentions the following:

The corrosion inhibition efficiencies of some triazole, oxadiazole and thiadiazole derivatives for steel in an acid medium have been studied by using AM1, PM3, MINDO/3 and MNDO semi-empirical SCF MO methods. Geometric structures, total neg. charge on the mol., highest occupied mol. energy level, lowest unoccupied mol. energy level, core-core repulsion, dipole moment, linear solvation energy terms, mol. volume and dipolar-polarization were correlated with the corrosion inhibition efficiency. Four equations were proposed to calculate the corrosion inhibition efficiency. The agreement with exptl. data was satisfactory, and the standard deviation between the calculated and exptl. results ranged between 闂?.03 and 闂?.18. The inhibition efficiency was closely related to the orbital energies and dipole moment. The correlation between quantum parameters and exptl. inhibition efficiency has been validated by single point calculations for the semi-empirical AM1 structures using B3LYP/6-31G** as a higher level of theory. The proposed equations were used to predict the corrosion inhibition efficiency of some related structures to select mols. of possible activity from a presumable library of compounds In the experiment, the researchers used many compounds, for example, 2,5-Di(pyridin-4-yl)-1,3,4-oxadiazole (cas: 15420-02-7SDS of cas: 15420-02-7).

2,5-Di(pyridin-4-yl)-1,3,4-oxadiazole (cas: 15420-02-7) 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. Many analogues of pyridine are known where N is replaced by other heteroatoms . Substitution of one C闂備胶鍋ㄩ崕鎻掝嚕?in pyridine with a second N gives rise to the diazine heterocycles (C4H4N2), with the names pyridazine, pyrimidine, and pyrazine.SDS of cas: 15420-02-7

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Directed ortho C-H borylation catalyzed using Cp*Rh(III)-NHC complexes was written by Thongpaen, Jompol;Schmid, Thibault E.;Toupet, Loic;Dorcet, Vincent;Mauduit, Marc;Basle, Olivier. And the article was included in Chemical Communications (Cambridge, United Kingdom) in 2018.Quality Control of 2-(m-Tolyl)pyridine This article mentions the following:

Cp*Rh(NHC) complexes I(R = ⁱBu, ⁱPr, Me), derived from L-amino acids, with bulky chiral bidentate NHC-carboxylate ligands were efficiently synthesized and fully characterized including solid-state structures. These unprecedented rhodium(III) complexes demonstrated high selectivity in pyridine-directed ortho-C-H borylation of arenes under mild conditions. In the experiment, the researchers used many compounds, for example, 2-(m-Tolyl)pyridine (cas: 4373-61-9Quality Control of 2-(m-Tolyl)pyridine).

2-(m-Tolyl)pyridine (cas: 4373-61-9) 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闂備胶鍋ㄩ崕鎻掝嚕?in pyridine with a second N gives rise to the diazine heterocycles (C4H4N2), with the names pyridazine, pyrimidine, and pyrazine.Quality Control of 2-(m-Tolyl)pyridine

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Selective cyclooxygenase-2 inhibitors: heteroaryl modified 1,2-diarylimidazoles are potent, orally active antiinflammatory agents was written by Khanna, Ish K.;Yu, Yi;Huff, Renee M.;Weier, Richard M.;Xu, Xiangdong;Koszyk, Francis J.;Collins, Paul W.;Cogburn, J. Nita;Isakson, Peter C.;Koboldt, Carol M.;Masferrer, Jaime L.;Perkins, William E.;Seibert, Karen;Veenhuizen, Amy W.;Yuan, Jinhua;Yang, Dai-Chang;Zhang, Yan Y.. And the article was included in Journal of Medicinal Chemistry in 2000.Category: pyridine-derivatives This article mentions the following:

A series of heteroaryl modified 1,2-diarylimidazoles has been synthesized and found to be potent and highly selective (1000-9000-fold) inhibitors of the human COX-2. 3-Pyridyl-derived COX-2 selective inhibitor I exhibited excellent activity in acute (carrageenan induced paw edema, ED₅₀ = 5.4 mg/kg) and chronic (adjuvant induced arthritis, ED₅₀ = 0.25 mg/kg) models of inflammation. The relatively long half-life of I in rat and dog prompted investigation of the pyridyl and other heteroaromatic systems containing potential metabolic functionalities. A number of substituted pyridyl and thiazole containing compounds. e.g., II, demonstrated excellent oral activity in every efficacy model evaluated. Several orally active diarylimidazoles exhibited desirable pharmacokinetics profiles and showed no GI toxicity in the rat up to 100 mg/kg in both acute and chronic models. The paper describes facile and practical syntheses of the targeted diarylimidazoles. The structure-activity relationships and antiinflammatory properties of a series of diarylimidazoles are discussed. In the experiment, the researchers used many compounds, for example, 4-Methylpicolinonitrile (cas: 1620-76-4Category: pyridine-derivatives).

4-Methylpicolinonitrile (cas: 1620-76-4) belongs to pyridine derivatives. The ring atoms in the pyridine molecule are sp2-hybridized. The nitrogen is involved in the 闂?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 闂?bonds. 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. Category: pyridine-derivatives

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Borane-Catalyzed Reduction of Pyridines via a Hydroboration/Hydrogenation Cascade was written by Yang, Zhao-Ying;Luo, Heng;Zhang, Ming;Wang, Xiao-Chen. And the article was included in ACS Catalysis in 2021.Reference of 89978-52-9 This article mentions the following:

A method for a B(C₆F₅)₃-catalyzed hydroboration/hydrogenation cascade reduction of 2,3-disubstituted pyridines to afford piperidine derivatives I [R = Me, Ph, 2-furyl, etc.; R¹ = Me, OH, Ph, etc.; R² = H, nosyl; R³ = H, Me; R⁴ = H, Me, Ph, etc.] in high yields with high cis selectivity was reported. Mechanistic studies indicated that the pyridine substrates and the piperidine products sequentially acted as bases in cooperation with B(C₆F₅)₃ to split H₂. The broad functional group tolerance of the method allowed its use for the synthesis of some biol. active mols. In the experiment, the researchers used many compounds, for example, Ethyl 2-bromoisonicotinate (cas: 89978-52-9Reference of 89978-52-9).

Ethyl 2-bromoisonicotinate (cas: 89978-52-9) 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. Many analogues of pyridine are known where N is replaced by other heteroatoms . Substitution of one C闂備胶鍋ㄩ崕鎻掝嚕?in pyridine with a second N gives rise to the diazine heterocycles (C4H4N2), with the names pyridazine, pyrimidine, and pyrazine.Reference of 89978-52-9

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Solvation Model for Chloroform Based on Class IV Atomic Charges was written by Giesen, David J.;Chambers, Candee C.;Cramer, Christopher J.;Truhlar, Donald G.. And the article was included in Journal of Physical Chemistry B in 1997.Recommanded Product: 4-Hexylpyridine This article mentions the following:

We present a parametrization of the SM5.4 solvation model, previously applied to aqueous solutions and general organic solvents, for predicting free energies of solvation in chloroform. As in all SM5 models, the calculations are based on a set of geometry-based functional forms for parameterizing at. surface tensions of organic solutes. In particular, the at. surface tensions depend in some cases on distances to nearby atoms. Combining the at. surface tensions with electrostatic effects included in a Fock operator by the generalized Born model enables one to calculate free energies of solvation by a quantum mech. self-consistent reaction field method. At. charges are obtained by both the AM1-CM1A and PM3-CM1P class IV charge models, which yield similar results, and hence the same at. radii and similar surface tension coefficients are used with both charge models. Exptl. free energies of solvation and free energies of transfer from aqueous solution are used to parametrize the theory for chloroform. The parametrization is based on a set of 205 neutral solutes containing H, C, N, O, F, S, Cl, Br, and I that we used previously to parameterize a model for general organic solvents plus 32 addnl. solutes added for this study. For the present parameterization, we used free energies of solvation in chloroform for 88 solutes, free energies of solvation in other solvents for 123 solutes, and free energies of transfer from water to chloroform for 26 other solutes. We obtained a mean unsigned error in the free energies of solvation in chloroform of 0.43 kcal/mol using CM1A at. charges and 0.34 kcal/mol using CM1P at. charges. In the experiment, the researchers used many compounds, for example, 4-Hexylpyridine (cas: 27876-24-0Recommanded Product: 4-Hexylpyridine).

4-Hexylpyridine (cas: 27876-24-0) belongs to pyridine derivatives. The ring atoms in the pyridine molecule are sp2-hybridized. The nitrogen is involved in the 闂?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 闂?bonds. Halopyridines are particularly attractive synthetic building blocks in a variety of cross-coupling methods, including the Suzuki-Miyaura cross-coupling reaction.Recommanded Product: 4-Hexylpyridine

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem