Tag: 100-200

Pyridine hydrochloride-catalyzed thiolation of alkenes: divergent synthesis of allyl and vinyl sulfides was written by Liu, Shiwen;Wang, Lili;Ma, Zhipeng;Zeng, Xiaojun;Xu, Bo. And the article was included in Organic Chemistry Frontiers in 2020.Quality Control of Pyridinehydrochloride This article mentions the following:

A highly efficient and practical protocol for the synthesis of allylic and vinyl sulfides via pyridinium chloride-catalyzed tandem thiolation-elimination of alkenes was described. This tandem protocol offered easy access to both allylic and 1,1-diarylvinyl sulfides under mild conditions with good to excellent yields and excellent functional group tolerance. In the experiment, the researchers used many compounds, for example, Pyridinehydrochloride (cas: 628-13-7Quality Control of Pyridinehydrochloride).

Pyridinehydrochloride (cas: 628-13-7) belongs to pyridine derivatives. Pyridine has a dipole moment and a weaker resonant stabilization than benzene (resonance energy 117 kJ·mol−1 in pyridine vs. 150 kJ·mol−1 in benzene). 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. Quality Control of Pyridinehydrochloride

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Selective imaging of hydrogen peroxide over peroxynitrite by a boronate-based fluorescent probe engineered via a doubly activated electrophilicity-increasing strategy was written by Tian, Di-Hua;Liu, Jun-Ru;Wang, Si-Yuan;Yan, Shuai;Chai, Zuo-Hu;Dai, Fang;Zhang, Shengxiang;Zhou, Bo. And the article was included in Sensors and Actuators, B: Chemical in 2022.Formula: C5H6ClN This article mentions the following:

Boronate-based fluorescent probes are widely used for the imaging of hydrogen peroxide (H₂O₂). However, their selectivity might be subjected to the interference of other reactive oxygen species, especially peroxynitrite (ONOO^–), due to the reaction of boronates with ONOO^– being several orders of magnitude faster than with H₂O₂. This work highlights a doubly activated electrophilicity-increasing strategy to develop a boronate-based fluorescent probe THMP for selective imaging of H₂O₂ over ONOO^–, where a boronate-modified pyridiniumylacrylonitrile is grafted on the 2-(2′-hydroxy-3′-methoxyphenyl) benzothiazole scaffold. Specifically, the boronate oxidation of THMP by H₂O₂ leads to the release of the free fluorophore THMP-N, triggering a ratiometric fluorescence response from red to green. The presence of a doubly activated electrophilic site on the carbon-carbon double bond of THMP, by both the strong electron-withdrawing cyano group and the pyridinium moiety, allows selective oxidative cleavage of the double bond by ONOO^– to an aldehyde HMBT-CHO, thereby excluding the interference of ONOO^– in monitoring H₂O₂. With the aid of the probe, we successfully visualized increased levels of H₂O₂ during ferroptosis of HepG2 cells, and burst of H₂O₂ in brains of live mice during cerebral ischemia reperfusion injury. In the experiment, the researchers used many compounds, for example, Pyridinehydrochloride (cas: 628-13-7Formula: C5H6ClN).

Pyridinehydrochloride (cas: 628-13-7) 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. 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: C5H6ClN

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Correlation and Estimation of Gas-Chloroform and Water-Chloroform Partition Coefficients by a Linear Free Energy Relationship Method was written by Abraham, Michael H.;Platts, James A.;Hersey, Anne;Leo, Albert J.;Taft, Robert W.. And the article was included in Journal of Pharmaceutical Sciences in 1999.COA of Formula: C11H17N This article mentions the following:

A linear free energy relation, LFER, has been used to correlate 150 values of gas-chloroform partition coefficients, as log L^chl with a standard deviation, sd, of 0.23 log units, a correlation coefficient r² of 0.985, and an F-statistic of 1919. The equation reveals that bulk chloroform is dipolar/polarizable, of little hydrogen-bond basicity, but as strong a hydrogen-bond acid as bulk methanol or bulk ethanol. However, the main influence on gaseous solubility in chloroform is due to solute-solvent London dispersion interactions. A slightly modified LFER has been used to correlate 302 values of water-chloroform partition coefficients, as log P_chl. The correlation equation predicts log P_chl for a further 34 compounds not used in the equation with sd = 0.17 log units. When the LFER is applied to all 335 log P_chl values, the resulting equation has sd = 0.25, r² = 0.971, and F = 2218. The importance of these results lies in the recent use of the water-chloroform system as a measure of solute lipophilicity and of recent calculations of the transfer of nucleic acids from water to chloroform. Furthermore if the water-chloroform system is to be generally used as a measure of solute lipophilicity in drug design, it will be of very considerable help to have a predictive procedure available. The authors have shown that the multiple linear regression anal. (MLRA) method is capable of correlating log P_chl values rather better than computational methods although the present MLRA method suffers from the possible lack of availability of the required descriptors. In the experiment, the researchers used many compounds, for example, 4-Hexylpyridine (cas: 27876-24-0COA of Formula: C11H17N).

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 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. Halopyridines are particularly attractive synthetic building blocks in a variety of cross-coupling methods, including the Suzuki-Miyaura cross-coupling reaction.COA of Formula: C11H17N

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Anticancer activity of novel pyrido[2,3-b]indolizine derivatives: the relevance of phenolic substituents was written by Boot, Arnoud;Brito, Alexandra;Van Wezel, Tom;Morreau, Hans;Costa, Marta;Proenca, Fernanda. And the article was included in Anticancer Research in 2014.Formula: C7H7ClN2 This article mentions the following:

Background/Aim: The potential of indolizine derivatives as anticancer agents has been shown through recent studies. Herein, we present our exptl. results, showing that pyrido[2,3-b]indolizine derivatives are effective against colorectal cancer (CRC) cell lines. Materials and Methods: Several pyrido[2,3-b]indolizine derivatives were synthesized and their anticancer potential was evaluated against three CRC cell lines and two normal fibroblast cultures. Results: Our experiments identified 4-(3,4)-dihydroxyphenyl)-2-phenylpyrido[2,3-b]indolizine-10-carbonitrile (4f) as being active against all CRC cell lines at concentrations non-cytotoxic against fibroblast cultures. Addnl., cell-cycle anal. indicated that pyrido[2,3-b]indolizines can affect cell-cycle progression, with treated cells accumulating in the S- and G₂/M-phase. Conclusion: The hydroxyl groups in both the 3- and 4- positions of the aromatic substituent on C4 of the indolizine nucleus are crucial for activity against CRC cell lines. Further manipulation of the number and position of hydroxyl substituents on the aromatic rings may lead to improved anticancer activity of this class of compounds In the experiment, the researchers used many compounds, for example, 1-(Cyanomethyl)pyridin-1-ium chloride (cas: 17281-59-3Formula: C7H7ClN2).

1-(Cyanomethyl)pyridin-1-ium chloride (cas: 17281-59-3) 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. Halopyridines are particularly attractive synthetic building blocks in a variety of cross-coupling methods, including the Suzuki-Miyaura cross-coupling reaction.Formula: C7H7ClN2

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Kinetics of the reaction of diphenylphosphinic hydrazide with phenyl isothiocyanate in the presence of benzopyridines was written by Yanchuk, N. I.. And the article was included in Zhurnal Obshchei Khimii in 1986.Application of 644-98-4 This article mentions the following:

The catalytic activity of pyridines and benzopyridines in the reaction of Ph₂P(O)NHNH₂ with PhNCS to give Ph₂P(O)NHNHCSNHPh decreased in the following order: isoquinoline > pyridine > 2,4-dimethypyridine > 2,4,6-trimethylpyrdine > 2-ethylpyridine > 2-picoline > quinoline > 2-isopropylpyridine > acridine > 2,6-dimethylpyridine > quinaldine. In the experiment, the researchers used many compounds, for example, 2-Isopropylpyridine (cas: 644-98-4Application of 644-98-4).

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

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Rhodium-Catalyzed CxS and CxN Functionalization of Arenes: Combination of CxH Activation and Hypervalent Iodine Chemistry was written by Wang, Fen;Yu, Xinzhang;Qi, Zisong;Li, Xingwei. And the article was included in Chemistry – A European Journal in 2016.Synthetic Route of C12H11N This article mentions the following:

Rhodium-catalyzed sulfonylation, thioetherification, thiocyanation, and other heterofunctionalizations of arenes bearing a heterocyclic directing group were realized. The reaction proceeds by initial Rh^III-catalyzed CxH hyperiodination of arene at room temperature followed by uncatalyzed nucleophilic functionalization. A diaryliodonium salt was isolated as an intermediate, which represents umpolung of the arene substrate, in contrast to previous studies that suggested umpolung of the coupling partner. In the experiment, the researchers used many compounds, for example, 2-(m-Tolyl)pyridine (cas: 4373-61-9Synthetic Route of C12H11N).

2-(m-Tolyl)pyridine (cas: 4373-61-9) 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. Pyridine groups exist in countless molecules, and their applications include catalysis, drug design, molecular recognition, and natural product synthesis.Synthetic Route of C12H11N

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Rhodium-Catalyzed Synthesis of Multiaryl-substituted Naphthols via a Removable Directing Group was written by Wang, Lianhui;Yu, Yunliang;Yang, Mengqi;Kuai, Changsheng;Cai, Dingding;Yu, Jinfeng;Cui, Xiuling. And the article was included in Advanced Synthesis & Catalysis in 2017.SDS of cas: 4783-68-0 This article mentions the following:

Arene homologation employing internal alkynes ArCCAr (Ar = 4-methylphenyl, 3-fluorophenyl, 4-acetylphenyl, etc.) as coupling partners and 2-pyridyloxyl as directing group through dual C-H bond functionalization was accomplished using (pentamethylcyclopentadienyl)-rhodium(III) chloride dimer as a pre-catalyst. This protocol proved tolerant of synthetically valuable functional groups, and provided an expeditious access to highly congested naphthalene derivatives, e.g., I in moderate to good yields. Furthermore, the pyridyl moiety could be removed to furnish the versatile (OH)-free naphthols II (Ar = Ph, 3-fluorophenyl; R = H, 2-Me, 3-Me, 4-F). In the experiment, the researchers used many compounds, for example, 2-Phenoxypyridine (cas: 4783-68-0SDS of cas: 4783-68-0).

2-Phenoxypyridine (cas: 4783-68-0) 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.SDS of cas: 4783-68-0

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

In silico cytotoxicity estimation of ionic liquids based on their two- and three-dimensional structural descriptors was written by Fatemi, Mohammad H.;Izadiyan, Parisa. And the article was included in Monatshefte fuer Chemie in 2011.Formula: C7H7ClN2 This article mentions the following:

The cytotoxicity of a series of ionic liquids containing ammonium, pyrrolidinium, imidazolium, pyridinium, and piperidinium cations against leukemia rat cell line IPC-81 was estimated from their structural parameters using quant. structure-activity relationship methodol. Linear and nonlinear models were developed using genetic algorithm multiple linear regression and multilayer perceptron neural network approaches. Robustness and reliability of the constructed models were evaluated by internal, external, and Y-randomization procedures. Furthermore, the chem. applicability domain was determined via a leverage approach for each model. The results of this study revealed that the contribution of structural characteristics of the anionic parts of the studied ILs were fewer than of the cationic parts. In the experiment, the researchers used many compounds, for example, 1-(Cyanomethyl)pyridin-1-ium chloride (cas: 17281-59-3Formula: C7H7ClN2).

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. 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: C7H7ClN2

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

5-Pyrimidinols: Novel Chain-Breaking Antioxidants More Effective than Phenols was written by Pratt, Derek A.;DiLabio, Gino A.;Brigati, Giovanni;Pedulli, Gian Franco;Valgimigli, Luca. And the article was included in Journal of the American Chemical Society in 2001.Reference of 51834-97-0 This article mentions the following:

On transition from phenol → 3-pyridinol → 5-pyrimidinol the IP increased by 24.3 kcal/mol, but the O-H BDE by only 2.5 kcal/mol (substituent effects were conserved in the 3 series), suggesting that 5-pyrimidinols should be effective H-atom donors that are more stable to air oxidation than similarly substituted phenols. Thus, 2-(dimethylamino)-4,6-dimethyl-5-pyrimidinol was prepared and exhibited a lower O-H BDE and higher IP than α-tocopherol. The 5-pyrimidinols reacted substantially faster with alkyl radicals than the corresponding phenols, and in the reaction with peroxyl radicals the two 5-pyrimidinols evaluated reacted at the same and 1/3 the rate of the corresponding phenol. In the experiment, the researchers used many compounds, for example, 5-Hydroxy-2-methoxylpyridine (cas: 51834-97-0Reference of 51834-97-0).

5-Hydroxy-2-methoxylpyridine (cas: 51834-97-0) 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.Reference of 51834-97-0

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Ruthenium-catalyzed ortho-selective C_Ar-H amination of heteroaryl arenes with di-tert-butyldiaziridinone was written by Gou, Xue-Ya;Li, Yuke;Wang, Xin-Gang;Liu, Hong-Chao;Zhang, Bo-Sheng;Zhao, Jia-Hui;Zhou, Zhao-Zhao;Liang, Yong-Min. And the article was included in Chemical Communications (Cambridge, United Kingdom) in 2019.HPLC of Formula: 4373-61-9 This article mentions the following:

Application of an oxidative amination reagent (di-tert-butyldiaziridinone) to the Ru₃(CO)₁₂-catalyzed ortho-selective CAr-H amination reaction was described. This strategy showed good functional group compatibility with various phenyl-substituted N-heterocycles, including biol. active substrates, thus providing synthetic potential for this methodol. Mechanistic studies showed that the reaction process involves an octahedral ruthenium species, and the carbon monoxide ligand plays a crucial role in the C-H activation. In the experiment, the researchers used many compounds, for example, 2-(m-Tolyl)pyridine (cas: 4373-61-9HPLC of Formula: 4373-61-9).

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. 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. HPLC of Formula: 4373-61-9

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem