Month: December 2022

Novel Ligustrazine-Based Analogs of Piperlongumine Potently Suppress Proliferation and Metastasis of Colorectal Cancer Cells in Vitro and in Vivo was written by Zou, Yu;Zhao, Di;Yan, Chang;Ji, Yanpeng;Liu, Jin;Xu, Jinyi;Lai, Yisheng;Tian, Jide;Zhang, Yihua;Huang, Zhangjian. And the article was included in Journal of Medicinal Chemistry in 2018.Electric Literature of C8H12N2O This article mentions the following:

Piperlongumine 1 increases reactive oxygen species (ROS) levels and preferably induces cancer cell apoptosis by triggering different pathways. However, the poor solubility of 1 limits its intensive investigation and clin. application. Ligustrazine possesses a water-soluble pyrazine skeleton and can inhibit proliferation and metastasis of cancer cells. We synthesized compound I by replacement of the trimethoxyphenyl of 1 with ligustrazine moiety and further introduced 2-Cl, -Br, and -I to I for synthesis of 4-6, resp. Compound II possessed 14-fold greater aqueous solubility than 1 and increased ROS levels in colorectal cancer HCT-116 cells. Addnl., II preferably inhibited proliferation, migration, invasion, and heteroadhesion of HCT-116 cells. Treatment with II suppressed tumor growth and lung metastasis in vivo and prolonged the survival of tumor-bearing mice. Furthermore, II mitigated TGF-β1-induced epithelial-mesenchymal transition and Wnt/β-catenin activation by inhibiting the Akt and GSK-3β phosphorylation in HCT-116 cells. Collectively, II displayed significant antiproliferation and antimetastasis activities, superior to 1. In the experiment, the researchers used many compounds, for example, (3,5,6-Trimethylpyrazin-2-yl)methanol (cas: 75907-74-3Electric Literature of C8H12N2O).

(3,5,6-Trimethylpyrazin-2-yl)methanol (cas: 75907-74-3) belongs to pyrazine derivatives. Pyrazine is a symmetrical molecule with point group D2h. Pyrazine is less basic than pyridine, pyridazine and pyrimidine. Pyrazine-based skeletons were incorporated into agents targeting a range of ailments. Many derivatives were synthesized and evaluated as potential cancer treatments.Electric Literature of C8H12N2O

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electrophysiological studies of pyridine-sensitive units on the crayfish walking leg. I. Characteristics of stimulatory molecules was written by Hatt, H.;Schmiedel-Jakob, I.. And the article was included in Journal of Comparative Physiology, A: Sensory, Neural, and Behavioral Physiology in 1984.Computed Properties of C7H5N3 This article mentions the following:

Pyridine-sensitive units located on the walking legs of the crayfish Austropotamobius torrentium were studied by extracellular recording of the action potentials of single afferent fibers. To characterize the sensitivity and specificity of the pyridine receptor, 79 pyridine analogs and other related substances were tested on 70 neurons. The maximum impulse frequency of the response was used to construct dose-response curves. The effectiveness of stimulatory substances was characterized at the half-maximal-response frequency, K_M. The effectiveness rank order of the substances was the same for all units tested. The most effective substances were: pyrazinecarboxamide > 3-acetylpyridine > nicotinamide > pyridine-3-aldoxime, with K_M values of 1.5 × 10^-6, 4 × 10^-6, 10^-5, and 4 × 10^-5M, resp. The inferred structural requirements for an optimal stimulatory mol. are that it have an N-containing aromatic ring system with a specific substituent in the m position. In the experiment, the researchers used many compounds, for example, Pyrido[2,3-b]pyrazine (cas: 322-46-3Computed Properties of C7H5N3).

Pyrido[2,3-b]pyrazine (cas: 322-46-3) belongs to pyrazine derivatives. Pyrazine heterocycles and their benzo derivatives possess many interesting properties, including chemical reactivity profiles, and have diverse applications in total synthesis, medicine, chemical biology, materials, dyes, and imaging. Pyrazines are chemical compounds (technically called “methoxypyrazines”) found in grape skin and stems that are responsible for many “green” flavors in wine. Levels of pyrazines are dependent on viticultural practices, climate, and grape variety.Computed Properties of C7H5N3

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Correlation of proton shifts of pyrazines with substituent constants was written by Marx, Gerard S.;Spoerri, Paul E.. And the article was included in Journal of Organic Chemistry in 1972.Electric Literature of C7H8N2O2 This article mentions the following:

A study of the PMR spectra of monosubstituted pyrazines in Me2SO indicated that the assigned peak values of the ortho, meta, and para protons correlated quite well with substituent constants A substituent-ring second-order mesomeric interaction explains the correlation of the proton meta to electron-donating substituents. In the experiment, the researchers used many compounds, for example, Ethyl pyrazine-2-carboxylate (cas: 6924-68-1Electric Literature of C7H8N2O2).

Ethyl pyrazine-2-carboxylate (cas: 6924-68-1) belongs to pyrazine derivatives. Pyrazine is an N-heterocyclic moiety, and it can be easily prepared from ethylenediamine and 1,2-diketone, α-hydroxyketone, α-methyl ketone. Pyrazines undergo nearly all of the same reactions as pyrimidines, from nucleophilic substitution (SNAr) to palladium-catalyzed cross coupling reactions.Electric Literature of C7H8N2O2

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthesis of pyrazinecarbonyl thiosemicarbazides was written by Wang, Rui;Jin, Liren;Wu, Xiuqin;Huang, Yuchu;Wu, Chunying;Wang, Yanjun. And the article was included in Zhongguo Yaoke Daxue Xuebao in 1991.Recommanded Product: 6924-68-1 This article mentions the following:

Title compounds I (R = allyl, cyclohexyl, Ph, substituted Ph) were prepared in 53-96% yield by refluxing 2-pyrazinecarboxylic hydrazide with RNCS in MeCN. I (R = allyl) inhibited the growth of Pseudomonas aeruginosa at 25 μg/mL. In the experiment, the researchers used many compounds, for example, Ethyl pyrazine-2-carboxylate (cas: 6924-68-1Recommanded Product: 6924-68-1).

Ethyl pyrazine-2-carboxylate (cas: 6924-68-1) belongs to pyrazine derivatives. Pyrazine has the elements of symmetry for the point group D2h. It has three mutually perpendicular two-fold axes. It also has three mutually perpendicular planes of symmetry. As a result, pyrazine also has a centre of symmetry. Pyrazine heterocycles and their benzo derivatives possess many interesting properties, including chemical reactivity profiles, and have diverse applications in total synthesis, medicine, chemical biology, materials, dyes, and imaging.Recommanded Product: 6924-68-1

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Hydrolysis kinetics of 2-bromomethyl-3,5,6-trimethylpyrazine was written by Ye, Deyong;Wang, Shuli;Yang, Chuyao;Jin, Jichun. And the article was included in Huadong Ligong Daxue Xuebao in 1995.Quality Control of (3,5,6-Trimethylpyrazin-2-yl)methanol This article mentions the following:

The rates of hydrolysis of 2-bromomethyl-3,5,6-trimethylpyrazine to corresponding hydroxymethyl compound at 60 °C and ionic strength μ = 0.15 over the pH range from 1 to 11 in buffer solutions were determined by means of HPLC. The reactions were treated following a apparent first-order kinetic equation, the first-order and the second-order reaction rate constants for the substrate and the first-order reaction rate constant for the substrate conjugated acid were obtained. The mechanisms of the hydrolysis were proposed to be S_N1 and S_N2. In the experiment, the researchers used many compounds, for example, (3,5,6-Trimethylpyrazin-2-yl)methanol (cas: 75907-74-3Quality Control of (3,5,6-Trimethylpyrazin-2-yl)methanol).

(3,5,6-Trimethylpyrazin-2-yl)methanol (cas: 75907-74-3) belongs to pyrazine derivatives. Pyrazines are volatile compounds that are used in the cosmetic, food, flavor, and fragrance industries. Substituted pyrazines have been found as subunits of multiple synthetically constructed therapeutic agents, as well as several natural products.Quality Control of (3,5,6-Trimethylpyrazin-2-yl)methanol

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electron-Deficient Heteroarenium Salts: An Organocatalytic Tool for Activation of Hydrogen Peroxide in Oxidations was written by Sturala, Jiri;Bohacova, Sona;Chudoba, Josef;Metelkova, Radka;Cibulka, Radek. And the article was included in Journal of Organic Chemistry in 2015.Application of 6924-68-1 This article mentions the following:

A series of monosubstituted pyrimidinium and pyrazinium triflates and 3,5-disubstituted pyridinium triflates were prepared and tested as simple catalysts of oxidations with hydrogen peroxide, using sulfoxidation as a model reaction. Their catalytic efficiency strongly depends on the type of substituent and is remarkable for derivatives with an electron-withdrawing group, showing reactivity comparable to that of flavinium salts which are the prominent organocatalysts for oxygenations. Because of their high stability and good accessibility, 4-(trifluoromethyl)pyrimidinium and 3,5-dinitropyridinium triflates are the catalysts of choice and were shown to catalyze oxidation of aliphatic and aromatic sulfides to sulfoxides, giving quant. conversions, high preparative yields and excellent chemoselectivity. The high efficiency of electron-poor heteroarenium salts is rationalized by their ability to readily form adducts with nucleophiles, as documented by low pK_R+ values (pK_R+ < 5) and less neg. reduction potentials (E_red > -0.5 V). Hydrogen peroxide adducts formed in situ during catalytic oxidation act as substrate oxidizing agents. The Gibbs free energies of oxygen transfer from these heterocyclic hydroperoxides to thioanisole, obtained by calculations at the B3LYP/6-311++g(d,p) level, showed that they are much stronger oxidizing agents than alkyl hydroperoxides and in some cases are almost comparable to derivatives of flavin hydroperoxide acting as oxidizing agents in monooxygenases. In the experiment, the researchers used many compounds, for example, Ethyl pyrazine-2-carboxylate (cas: 6924-68-1Application of 6924-68-1).

Ethyl pyrazine-2-carboxylate (cas: 6924-68-1) belongs to pyrazine derivatives. Pyrazines are part of several biologically active polycyclic compounds; examples are quinoxalines, phenazines; and the bio-luminescent natural products pteridines, flavins, and their derivatives. A large number of pyrazine derivatives are known for their antitumor, antibiotic, anticonvulsant, antituberculosis, and diuretic activities.Application of 6924-68-1

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Preparation of New Electron-Accepting π-Conjugated Polyquinoxalines. Chemical and Electrochemical Reduction, Electrically Conducting Properties, and Use in Light-Emitting Diodes was written by Yamamoto, Takakazu;Sugiyama, Kiyoshi;Kushida, Takashi;Inoue, Tetsuji;Kanbara, Takaki. And the article was included in Journal of the American Chemical Society in 1996.HPLC of Formula: 148231-12-3 This article mentions the following:

Dehalogenation polycondensation of 5,8-dibromoquinoxaline derivatives and 2,6-dibromoquinoxaline with zero-valent Ni complex gives a series of π-conjugated polyquinoxalines with mol. weight of 6 × 10³-260 × 10³. The polymers are electrochem. reduced (or n-doped) with an E° value of -1.75 to -2.35 V vs Ag/Ag⁺ and converted into elec. conducting materials with a conductivity of 1 × 10^-4 to 7 × 10^-3 S cm^-1 by chem. reduction Poly(quinoxaline-5,8-diyl)s with aromatic substituents give strong fluorescence with emission peaks at 450-520 nm in solutions as well as in cast films. A light-emitting diode (LED), ITO/polymer/Mg(Ag) (polymer = poly(2,3-diphenylquinoxaline-5,8-diyl)), emits blue-green light (λ_max at about 500 nm). Introduction of hole-transporting layers such as vacuum-deposited or spin-coated thin layers of poly(thiophene-2,5-diyl), poly(p-phenylene), and poly(N-vinylcarbazole) between ITO and the light-emitting layer enhances electroluminescence efficiency by about 2 orders of magnitude. Polyquinoxalines have an ionization potential of 5.83 ± 0.11 eV and a band gap of 2.56 ± 0.26 eV. In the experiment, the researchers used many compounds, for example, 5,8-Dibromoquinoxaline (cas: 148231-12-3HPLC of Formula: 148231-12-3).

5,8-Dibromoquinoxaline (cas: 148231-12-3) belongs to pyrazine derivatives. Pyrazine derivatives have antitumor, antibiotic, anticonvulsant, antituberculous and diuretic effects as well as kinase, enzymatic and potent tubulin and FtsZ polymerization inhibitory activities. Substituted pyrazines have been found as subunits of multiple synthetically constructed therapeutic agents, as well as several natural products.HPLC of Formula: 148231-12-3

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Direct Amidation of Esters by Ball Milling was written by Nicholson, William I.;Barreteau, Fabien;Leitch, Jamie A.;Payne, Riley;Priestley, Ian;Godineau, Edouard;Battilocchio, Claudio;Browne, Duncan L.. And the article was included in Angewandte Chemie, International Edition in 2021.Formula: C7H8N2O2 This article mentions the following:

The direct mechanochem. amidation of esters RC(O)OR¹ (R = Cy, Ph, pyridin-2-yl, etc.; R¹ = Me, Et) by ball milling is described. The operationally simple procedure requires an ester, amines R²NHR³ (R² = H, Me, Et; R³ = i-Pr, Ph, 2,4,6-trimethylphenyl, etc.; R²R³ = -(CH₂)₂O(CH₂)₂-, -(CH₂)₅-, -(CH₂)₆-, etc.) and 1,2,3,4-tetrahydroquinoline, and substoichiometric KOtBu, and was used to prepare a large and diverse library of 78 amide structures RC(O)N(R²)R³ and (3,4-dihydroquinolin-1(2H)-yl)(phenyl)methanone with modest to excellent efficiency. Heteroaromatic and heterocyclic components are specifically shown to be amenable to this mechanochem. protocol. This direct synthesis platform has been applied to the synthesis of active pharmaceutical ingredients (APIs) and agrochems. as well as the gram-scale synthesis of an active pharmaceutical, all in the absence of a reaction solvent. In the experiment, the researchers used many compounds, for example, Ethyl pyrazine-2-carboxylate (cas: 6924-68-1Formula: C7H8N2O2).

Ethyl pyrazine-2-carboxylate (cas: 6924-68-1) belongs to pyrazine derivatives. Pyrazines are volatile compounds that are used in the cosmetic, food, flavor, and fragrance industries. Pyrazine heterocycles and their benzo derivatives possess many interesting properties, including chemical reactivity profiles, and have diverse applications in total synthesis, medicine, chemical biology, materials, dyes, and imaging.Formula: C7H8N2O2

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Discovery of a novel chemotype of potent human ENaC blockers using a bioisostere approach. Part 1: Quaternary amines was written by Hunt, Thomas;Atherton-Watson, Hazel C.;Axford, Jake;Collingwood, Stephen P.;Coote, Kevin J.;Cox, Brian;Czarnecki, Sarah;Danahay, Henry;Devereux, Nick;Howsham, Catherine;Hunt, Peter;Paddock, Victoria;Paisley, Derek;Young, Alice. And the article was included in Bioorganic & Medicinal Chemistry Letters in 2012.Name: Methyl 3,5-diamino-6-chloropyrazine-2-carboxylate This article mentions the following:

We report the identification of a novel series of human epithelial sodium channel (ENaC) blockers that are structurally distinct from the pyrazinoyl guanidine chemotype found in prototypical ENaC blockers such as amiloride. Following a rational design hypothesis a series of quaternary amines were prepared and evaluated for their ability to block ion transport via ENaC in human bronchial epithelial cells (HBECs). Compound 11 has an IC₅₀ of 200 nM and is efficacious in the Guinea-pig tracheal p.d. (TPD) model of ENaC blockade with an ED₅₀ of 44 μg kg^-1 at 1 h. As such, pyrazinoyl quaternary amines represent the first examples of a promising new class of human ENaC blockers. In the experiment, the researchers used many compounds, for example, Methyl 3,5-diamino-6-chloropyrazine-2-carboxylate (cas: 1458-01-1Name: Methyl 3,5-diamino-6-chloropyrazine-2-carboxylate).

Methyl 3,5-diamino-6-chloropyrazine-2-carboxylate (cas: 1458-01-1) belongs to pyrazine derivatives. Pyrazines are volatile compounds that are used in the cosmetic, food, flavor, and fragrance industries. Substituted pyrazines have been found as subunits of multiple synthetically constructed therapeutic agents, as well as several natural products.Name: Methyl 3,5-diamino-6-chloropyrazine-2-carboxylate

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

The accessibility of nitrogen sites makes a difference in selective CO₂ adsorption of a family of isostructural metal-organic frameworks was written by Song, Chengling;Hu, Jiayi;Ling, Yajing;Feng, YunLong;Krishna, Rajamani;Chen, De-li;He, Yabing. And the article was included in Journal of Materials Chemistry A: Materials for Energy and Sustainability in 2015.Electric Literature of C8H4Br2N2 This article mentions the following:

By using three rigid diisophthalate organic linkers incorporating different numbers and orientations of Lewis basic nitrogen atoms into the spacers between two terminal isophthalate moieties, namely, 5,5′-(quinoline-5,8-diyl)-diisophthalate, 5,5′-(isoquinoline-5,8-diyl)-diisophthalate, and 5,5′-(quinoxaline-5,8-diyl)-diisophthalate, a family of isostructural copper-based metal-organic frameworks, ZJNU-43, ZJNU-44, and ZJNU-45, were successfully solvothermally synthesized and structurally characterized by single-crystal X-ray diffraction. The three MOFs, after activation, exhibited almost the same porosities but distinctly different CO₂ adsorption properties. At room temperature and 1 atm, the adsorption capacities for CO₂ reached 103, 116, and 107 cm³ (STP) g^-1 for ZJNU-43a, ZJNU-44a, and ZJNU-45a, resp. Furthermore, Ideal Adsorbed Solution Theory (IAST) and simulated breakthrough analyses indicated that ZJNU-44a bearing much more easily accessible nitrogen sites is the best among the three MOFs for the separation of the following two binary gas mixtures at 296 K, i.e., 50/50 CO₂/CH₄ and 15/85 CO₂/N₂ gas mixtures, indicating that the accessibility of nitrogen sites plays a much more crucial role, which is further confirmed by comprehensive quantum chem. calculations This work demonstrates that the CO₂ adsorption properties of MOFs depend not only on the number of Lewis basic nitrogen sites but also more importantly on their accessibility. In the experiment, the researchers used many compounds, for example, 5,8-Dibromoquinoxaline (cas: 148231-12-3Electric Literature of C8H4Br2N2).

5,8-Dibromoquinoxaline (cas: 148231-12-3) belongs to pyrazine derivatives. Pyrazine is an N-heterocyclic moiety, and it can be easily prepared from ethylenediamine and 1,2-diketone, α-hydroxyketone, α-methyl ketone. A number of pyrazine-based derivatives were used as dyes or fluorescent probes.Electric Literature of C8H4Br2N2

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem