Day: January 6, 2023

The effect of alkyl chain length on the degradation of alkylimidazolium- and pyridinium-type ionic liquids in a Fenton-like system was written by Siedlecka, Ewa M.;Stepnowski, Piotr. And the article was included in Environmental Science and Pollution Research in 2009.Formula: C10H16ClN This article mentions the following:

Background, aim, and scope Ionic liquids are regarded as essentially “green” chems. because of their insignificant vapor pressure and, hence, are a good alternative to the emissions of toxic conventional volatile solvents. Not only because of their attractive industrial applications, but also due to their very high stability, ionic liquids could soon become persistent contaminants of technol. wastewaters and, moreover, break through into natural waters following classical treatment systems. The removal of harmful organic pollutants has forced the development of new methodologies known as advanced oxidation processes (AOPs). Among them, the Fenton and Fenton-like reactions are usually modified by the use of a higher hydrogen peroxide concentration and through different catalysts. The aim of this study was to assess the effect of hydrogen peroxide concentration on degradation rates in a Fenton-like system of alkylimidazolium ionic liquids with alkyl chains of varying length and 3-methyl-N-butylpyridinium chloride. Materials and methods The ionic liquids were oxidized in dilute aqueous solution in the presence of two different concentrations of hydrogen peroxide. All reactions were performed in the dark to prevent photoreduction of Fe(III). The concentrations of ionic liquids during the process were monitored with high-performance liquid chromatog. Preliminary degradation pathways were studied with the aid of ¹H NMR. Results Degradation of ionic liquids in this system was quite effective. Increasing the H₂O₂ concentration from 100 to 400 mM improved ionic liquid degradation from 57-84% to 87-100% after 60 min reaction time. Resistance to degradation was weaker, the shorter the alkyl chain. Discussion The compound omimCl was more resistant to oxidation then other compounds, which suggests that the oxidation rates of imidazolium ionic liquids by OH· are structure-dependent and are correlated with the n-alkyl chain length substituted at the N-1-position. The level of degradation was dependent on the type of head group. Replacing the imidazolium head group with pyridinium increased resistance to degradation Nonetheless, lengthening the alkyl chain from four to eight carbons lowered the rate of ionic liquid degradation to a greater extent than changing the head group from imidazolium to pyridinium. 1H-NMR spectra show, in the first stage of degradation, that it is likely that radical attack is nonspecific, with any one of the carbon atoms in the ring and the n-alkyl chain being susceptible to attack. Conclusions The proposed method has proven to be an efficient and reliable method for the degradation of imidazolium ionic liquids by a Fenton-like reagent deteriorated with lengthening n-alkyl substituents and by replacing the imidazolium head group with pyridinium. The enhanced resistance of 1-butyl-3-methylpyridinium chloride when the resistance of imidazolium ionic liquids decreases with increasing H₂O₂ concentration is probably indicative of a change in the degradation mechanism in a vigorous Fenton-like system. H-NMR spectra showed, in the first stage of degradation, that radical attack is nonspecific, with any one of the carbon atoms in the ring and the n-alkyl chain being susceptible to attack. In the experiment, the researchers used many compounds, for example, 1-Butyl-3-methylpyridinium Chloride (cas: 125652-55-3Formula: C10H16ClN).

1-Butyl-3-methylpyridinium Chloride (cas: 125652-55-3) 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.Formula: C10H16ClN

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

QSAR studies related to toxicity of aromatic compounds on Tetrahymena pyriformis was written by Laszlo, Tarko;Beteringhe, Adrian. And the article was included in QSAR & Combinatorial Science in 2006.Reference of 15128-90-2 This article mentions the following:

Results of some QSAR studies in which the training set contained aromatic compounds with toxic effect on Tetrahymena pyriformis are presented. The QSAR studies reveal the existence of two classes of compounds – with and without hydrogen bonds – for which the calculation of some QSAR separated equations are recommended. QSAR equations obtained for the two classes of aromatic compounds have good predictive powers: N = 87, p = 6, r² = 0.7962, s = 0.3178, and N = 113, p = 5, r² = 0.8950, s = 0.2637, resp. For the compounds with hydrogen bonds, “moment of inertia B” and “QSPR of percentage of mass fragments” are mol. characteristics with a powerful influence on toxicity values, and log K_ow has a moderate influence. For compounds without hydrogen bonds “bonds number weighted total energy” and “LUMO-HOMO gap weighted mol. volume” are the mol. characteristics with a powerful effect on toxicity values, and topol. descriptor AAA has a moderate effect. In the experiment, the researchers used many compounds, for example, 3-Hydroxy-6-methyl-2-nitropyridine (cas: 15128-90-2Reference of 15128-90-2).

3-Hydroxy-6-methyl-2-nitropyridine (cas: 15128-90-2) belongs to pyridine derivatives. The pyridine ring occurs in many important compounds, including agrochemicals, pharmaceuticals, and vitamins. 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.Reference of 15128-90-2

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Identification of Isoform 2 Acid-Sensing Ion Channel Inhibitors as Tool Compounds for Target Validation Studies in CNS was written by Bencheva, Leda Ivanova;De Matteo, Marilenia;Ferrante, Luca;Ferrara, Marco;Prandi, Adolfo;Randazzo, Pietro;Ronzoni, Silvano;Sinisi, Roberta;Seneci, Pierfausto;Summa, Vincenzo;Gallo, Mariana;Veneziano, Maria;Cellucci, Antonella;Mazzocchi, Nausicaa;Menegon, Andrea;Di Fabio, Romano. And the article was included in ACS Medicinal Chemistry Letters in 2019.COA of Formula: C6H3FN2 This article mentions the following:

Acid-sensing ion channels (ASICs) are a family of ion channels permeable to cations and largely responsible for the onset of acid-evoked ion currents both in neurons and in different types of cancer cells, thus representing a potential target for drug discovery. Owing to the limited attention ASIC2 has received so far, an exploratory program was initiated to identify ASIC2 inhibitors using diminazene, a known pan-ASIC inhibitor, as a chem. starting point for structural elaboration. The performed exploration enabled the identification of a novel series of ASIC2 inhibitors. In particular, compound I is a brain penetrant ASIC2 inhibitor endowed with an optimal pharmacokinetic profile. This compound may represent a useful tool to validate in animal models in vivo the role of ASIC2 in different neurodegenerative central nervous system pathologies. In the experiment, the researchers used many compounds, for example, 6-Fluoronicotinonitrile (cas: 3939-12-6COA of Formula: C6H3FN2).

6-Fluoronicotinonitrile (cas: 3939-12-6) 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. 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. COA of Formula: C6H3FN2

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Design of potent IGF1-R inhibitors related to bis-azaindoles was written by Nemecek, Conception;Metz, William A.;Wentzler, Sylvie;Ding, Fa-Xiang;Venot, Corinne;Souaille, Catherine;Dagallier, Anne;Maignan, Sebastien;Guilloteau, Jean-Pierre;Bernard, Francois;Henry, Alain;Grapinet, Sandrine;Lesuisse, Dominique. And the article was included in Chemical Biology & Drug Design in 2010.HPLC of Formula: 882033-66-1 This article mentions the following:

From an azaindole lead (I), identified in high throughput screen, a series of potent bis-azaindole inhibitors of IGF1-R have been synthesized using rational drug design and SAR based on an in silico binding mode hypothesis. Although the resulting compounds produced the expected improved potency, the model was not validated by the co-crystallization experiments with IGF1-R. General synthetic schemes for preparing the compounds tested are given in the paper. In the experiment, the researchers used many compounds, for example, 4-Chloro-5-fluoro-1H-pyrrolo[2,3-b]pyridine (cas: 882033-66-1HPLC of Formula: 882033-66-1).

4-Chloro-5-fluoro-1H-pyrrolo[2,3-b]pyridine (cas: 882033-66-1) 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.HPLC of Formula: 882033-66-1

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Syntheses, Crystal Structures, and Thermal Stability of Metal-Directed Co(II) and Cu(II) Coordination Assemblies with Mixed Ligands of 5-Methylisophthalic Acid and 2,5-Bis(4-Pyridyl)-1,3,4-Oxadiazole was written by Liu, Shang-Yuan;Chen, Jing;Li, Cheng-Peng. And the article was included in Synthesis and Reactivity in Inorganic, Metal-Organic, and Nano-Metal Chemistry in 2011.Category: pyridine-derivatives This article mentions the following:

Two mixed-ligand Co(II) and Cu(II) coordination complexes were prepared by using a similar hydrothermal method, from a bent dipyridyl building block 2,5-bis(4-pyridyl)-1,3,4-oxadiazole (4-bpo) and 5-methylisophthalic acid (H₂i.p.-CH₃). Complexes 1 and 2 show the distinct coordination structures, such as 1D polymeric ribbon and dinuclear paddle-wheel motif, resp. Furthermore, H-bonding interactions extend the coordination patterns into a 3D scaffold architecture for 1 and a 2D 2-fold entangled network of both polyrotaxane and polycatenane features for 2. The interesting structural architectures of such two complexes are mainly directed by the different coordination capability of metal ions, as well as the H-bonding interactions. In the experiment, the researchers used many compounds, for example, 2,5-Di(pyridin-4-yl)-1,3,4-oxadiazole (cas: 15420-02-7Category: pyridine-derivatives).

2,5-Di(pyridin-4-yl)-1,3,4-oxadiazole (cas: 15420-02-7) 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. 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

Rhodium(III)-Catalyzed Directed C-H Coupling with Methyl Trifluoroacrylate: Diverse Synthesis of Fluoroalkenes and Heterocycles was written by Gong, Tian-Jun;Xu, Meng-Yu;Yu, Shang-Hai;Yu, Chu-Guo;Su, Wei;Lu, Xi;Xiao, Bin;Fu, Yao. And the article was included in Organic Letters in 2018.SDS of cas: 4373-61-9 This article mentions the following:

An example of Rh-catalyzed C-H activation with Me trifluoroacrylate for the synthesis of fluoroolefins and heterocycles (benzoindolizines) is reported. The types of products were determined by the directing group. The benzoindolizines and fluoroolefins were obtained by using pyridine and pyrazole as the directing group, correspondingly. These transformations present a number of advantages, such as oxidant-free reaction conditions and broad functional group tolerance. Moreover, this reaction greatly extends the application of fluoroolefins. In the experiment, the researchers used many compounds, for example, 2-(m-Tolyl)pyridine (cas: 4373-61-9SDS of cas: 4373-61-9).

2-(m-Tolyl)pyridine (cas: 4373-61-9) 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. 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. SDS of cas: 4373-61-9

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Influence of Guest/Host Morphology on Room Temperature Phosphorescence Properties of Pure Organic Doped Systems was written by Liu, Xiaoqing;Pan, Yanyan;Lei, Yunxiang;Liu, Nannan;Dai, Wenbo;Liu, Miaochang;Cai, Zhengxu;Wu, Huayue;Huang, Xiaobo;Dong, Yuping. And the article was included in Journal of Physical Chemistry Letters in 2021.Recommanded Product: 91-02-1 This article mentions the following:

Guest/host phosphorescence materials have attracted much attention; traditionally, researchers have focused on the influence of the electronic properties and energy levels of the mols. on the phosphorescence activities. The effects of the morphol. on the phosphorescence are ignored. Three isoquinoline guests with different aliphatic rings and 3 hosts are selected to construct guest/host materials. The guests are dispersed in the host as clusters. The morphols. of the guest/host directly affect the phosphorescence. In these systems, the guests have strong intermol. interactions, which are beneficial to stabilize the triplet excitons; meanwhile, the hosts should have weak intermol. interactions with easily changed morphol. to accept the guest clusters, which synergistically ensure that the doped materials have excellent RTP properties. This is the 1st work focusing on the effect of mol. morphol. on the phosphorescence of guest/host systems. In the experiment, the researchers used many compounds, for example, Phenyl(pyridin-2-yl)methanone (cas: 91-02-1Recommanded Product: 91-02-1).

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. 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.Recommanded Product: 91-02-1

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Photoredox-catalysed regioselective synthesis of C-4-alkylated pyridines with N-(acyloxy)phthalimides was written by Zhang, Zhucheng;He, Qian;Zhang, Xiaofei;Yang, Chunhao. And the article was included in Organic & Biomolecular Chemistry in 2022.Recommanded Product: 2-Isopropylpyridine This article mentions the following:

A method of direct C-4 selective alkylation of pyridines under visible light irradiation at room temperature was reported using simple maleate-derived pyridinium salts as pyridine precursors and the readily available carboxylic acid-derived N-(acyloxy)phthalimides as alkyl radical precursors, affording good to excellent yields without using stoichiometric oxidants and acids. A broad range of primary, secondary and tertiary carboxylates were used as alkylation reagents. Oxidant and acid-sensitive functional groups were tolerated well. In the experiment, the researchers used many compounds, for example, 2-Isopropylpyridine (cas: 644-98-4Recommanded Product: 2-Isopropylpyridine).

2-Isopropylpyridine (cas: 644-98-4) 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. Halopyridines are particularly attractive synthetic building blocks in a variety of cross-coupling methods, including the Suzuki-Miyaura cross-coupling reaction.Recommanded Product: 2-Isopropylpyridine

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Qualitative and quantitative structure activity relationships for the inhibitory effects of cationic head groups, functionalized side chains and anions of ionic liquids on acetylcholinesterase was written by Arning, Juergen;Stolte, Stefan;Boeschen, Andrea;Stock, Frauke;Pitner, William-Robert;Welz-Biermann, Urs;Jastorff, Bernd;Ranke, Johannes. And the article was included in Green Chemistry in 2008.HPLC of Formula: 17281-59-3 This article mentions the following:

To contribute to a deeper insight into the hazard potential of ionic liquids to humans and the environment, an acetylcholinesterase (AchE) inhibition screening assay was used to identify toxicophore substructures and interaction potentials mediating enzyme inhibition. The pos. charged nitrogen atom, a widely delocalized aromatic system, and the lipophilicity of the side chains connected to the cationic head groups can be identified as the key structural elements in binding to the enzymes active site. With respect to this, the dimethylaminopyridinium, the quinolinium and the pyridinium head groups exhibit a very strong inhibitory potential to the enzyme with IC₅₀ values around 10 μM. In contrast, the polar and non-aromatic morpholinium head group is found to be only weakly inhibiting to the enzyme activity, with IC₅₀ values > 500 μM. The introduction of polar hydroxy, ether or nitrile functions into the alkyl side chain is shown to be a potent structural alteration to shift the corresponding ionic liquids to a lower inhibitory potential. Supporting this fact, for a series of imidazolium cations, a QSAR correlation was set up by the linear regression of the log IC₅₀ vs. the logarithm of the HPLC-derived lipophilicity parameter k₀. Addnl., a broad set of anion species (inorganic, organic and complex borate anions), commonly used as ionic liquid counterions, was tested and the vast majority exhibited no effect on AchE. Only the fluoride and fluoride containing anion species which readily undergo hydrolytic cleavage can be identified to act as AchE inhibitors. In the experiment, the researchers used many compounds, for example, 1-(Cyanomethyl)pyridin-1-ium chloride (cas: 17281-59-3HPLC of Formula: 17281-59-3).

1-(Cyanomethyl)pyridin-1-ium chloride (cas: 17281-59-3) 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. Pyridine derivatives are also useful as small-molecule α-helix mimetics that inhibit protein-protein interactions, as well as functionally selective GABA ligands.HPLC of Formula: 17281-59-3

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Design and Potency of Dual Soluble Epoxide Hydrolase/Fatty Acid Amide Hydrolase Inhibitors was written by Kodani, Sean D.;Wan, Debin;Wagner, Karen M.;Hwang, Sung Hee;Morisseau, Christophe;Hammock, Bruce D.. And the article was included in ACS Omega in 2018.Formula: C11H20N2O2S This article mentions the following:

Fatty acid amide hydrolase (FAAH) is responsible for regulating concentrations of the endocannabinoid arachidonoyl ethanolamide (AEA). Multiple FAAH inhibitors have been developed for clin. trials and have failed to demonstrate efficacy at treating pain, despite promising preclin. data. One approach towards increasing the efficacy of FAAH inhibitors is to concurrently inhibit other targets responsible for regulating pain. Here, the authors designed dual inhibitors targeting the enzymes FAAH and soluble epoxide hydrolase (sEH), which are targets previously shown to synergize at reducing inflammatory and neuropathic pain. Exploration of the sEH/FAAH inhibitor structure activity relationship started with PF-750, a FAAH inhibitor (IC₅₀ = 19 nM) that weakly inhibited sEH (IC₅₀ = 640 nM). Potency was optimized resulting in an inhibitor with improved potency on both targets (11, sEH IC₅₀ = 5 nM, FAAH IC₅₀ = 8 nM). This inhibitor demonstrated good target selectivity, pharmacokinetic properties (AUC = 1200 h*nM, t1/2=4.9 h in mice) and in vivo target engagement. In the experiment, the researchers used many compounds, for example, tert-Butyl 4-carbamothioylpiperidine-1-carboxylate (cas: 214834-18-1Formula: C11H20N2O2S).

tert-Butyl 4-carbamothioylpiperidine-1-carboxylate (cas: 214834-18-1) 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. 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.Formula: C11H20N2O2S

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem