Month: January 2023

Synthesis, structures, and spectroscopic properties of 3-aryl-5-(2-pyridyl)pyrazoles and related pyrazoles was written by Schowtka, Bjoern;Mueller, Christoph;Goerls, Helmar;Westerhausen, Matthias. And the article was included in Zeitschrift fuer Anorganische und Allgemeine Chemie in 2014.Recommanded Product: 6924-68-1 This article mentions the following:

3-Aryl-5-(2-pyridinyl)pyrazoles and related compounds I (R¹ = Ph, 4-MeC₆H₄, 3,4,5-Me₃C₆H₂, etc.; R² = 2-pyridinyl, 1-isoquinolinyl, 2-quinolinyl, etc.) were easily accessible via the reaction of the appropriate 1,3-diketone with hydrazine hydrate. The central pyrazole rings show a far-reaching equalization of the bond lengths. In the crystalline state dimeric and strand-like structures are observed due to the formation of intermol. N-H···N hydrogen bridges between the pyrazole N-H functionality and a pyrazole or pyridine base. The structures mainly depend on the steric demand of the aryl groups. Planar 3-aryl-5-(2-pyridinyl)pyrazoles also show π stacking, which reduces their solubility in common organic solvents. 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 is an N-heterocyclic moiety, and it can be easily prepared from ethylenediamine and 1,2-diketone, α-hydroxyketone, α-methyl ketone. Substituted pyrazines have been found as subunits of multiple synthetically constructed therapeutic agents, as well as several natural products.Recommanded Product: 6924-68-1

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

An efficient hydration of nitriles with ruthenium-supported heterogeneous catalyst in water under moderate conditions was written by Hussain, Muhammad Asif;Choi, Eun Ju;Maqbool, Adnan;Atif, Muhammad;Zeb, Hassan;Yeo, JaeGoo;Yu, Jung-A.;Cho, Yong-Hun;Noh, Moses;Kim, Jung Won. And the article was included in Journal of Industrial and Engineering Chemistry (Amsterdam, Netherlands) in 2021.Application of 89323-09-1 This article mentions the following:

A facile eco-friendly heterogeneous catalytic system has been developed for amide synthesis that further utilized in pharmaceutical and organic chem. The Ru/MnO₂ catalyst has shown outstanding and unprecedented activity for a wide range of aliphatic and benzylic nitriles in green solvent water at 60°C. The system has also exhibited a remarkable tolerance for selective hydration of heteroatom (e.g. nitrogen, oxygen and sulfur atoms) containing nitriles. Pharmaceutically important nicotinamides and pyrazinamide has been synthesized by hydration of the heteroat. nitriles with appreciable yields and selectivities. Moreover, the Ru/MnO₂ catalyst has employed water as a benign solvent, with more than 30,000 TONs and reusability five times after isolation from the reaction mixture by centrifugation and easy workup that established a path for green environmental and technol. acceptable protocol. In the experiment, the researchers used many compounds, for example, 5-Aminopyrazine-2-carboxamide (cas: 89323-09-1Application of 89323-09-1).

5-Aminopyrazine-2-carboxamide (cas: 89323-09-1) 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 “methoxypyrazinesâ€? found in grape skin and stems that are responsible for many “greenâ€?flavors in wine. Levels of pyrazines are dependent on viticultural practices, climate, and grape variety.Application of 89323-09-1

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Heterogeneous and homogeneous redox catalyzed reduction of some sulfilimines was written by Griggio, L.;Severin, M. G.. And the article was included in Journal of Electroanalytical Chemistry and Interfacial Electrochemistry in 1987.SDS of cas: 322-46-3 This article mentions the following:

The homogeneous and electrode 2-electron reduction of some sulfonylsulfilimines were investigated in order to obtain more quant. kinetic and thermodn. information. The 2 processes were analyzed on the basis of homogeneous redox catalysis and voltammetric results, resp. Both reactions were shown, in most cases, to be controlled by the 1st endergonic electron uptake. The kinetic data for the process were interpreted on the basis of simple theories for electron-transfer reactions, allowing intrinsic thermodn. and activation parameters of the charge-transfer steps to be estimated The results were found to be more consistent with the hypothesis of a simple outer-sphere electron transfer followed by a fast 1st-order reaction rather than with a concerted bond breaking-charge transfer step. No relevant differences were observed owing to the replacement of Et with Ph groups in the sulfilimine moiety, the substitution effect being apparent only from a thermodn. point of view. On the contrary, the introduction of a CN group in the sulfonyl moiety increased sensibly the stability of the intermediate radical anion. This caused the electrode process kinetics to be partially dependent on the radical anion decay, allowing the quant. evaluation of its lifetime. In the experiment, the researchers used many compounds, for example, Pyrido[2,3-b]pyrazine (cas: 322-46-3SDS of cas: 322-46-3).

Pyrido[2,3-b]pyrazine (cas: 322-46-3) belongs to pyrazine derivatives. Pyrazinesare six-membered aromatic heterocyclic organic compounds with two nitrogen atoms at 1,4-positions. Pyrazine is a weaker base (pKb = 13.4) than pyridine (pKb = 8.8), pyrimidine (pKb = 12.7). A number of pyrazine-based derivatives were used as dyes or fluorescent probes.SDS of cas: 322-46-3

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Vicarious nucleophilic substitution of hydrogen, bisannulation and competitive reactions of α-haloalkyl carbanions with bicyclic azaaromatic compounds was written by Makosza, Mieczyslaw;Golinski, Jerzy;Ostrowski, Stanislaw;Rykowski, Andrzej;Sahasrabudhe, Arvind B.. And the article was included in Chemische Berichte in 1991.HPLC of Formula: 322-46-3 This article mentions the following:

Carbanions of RR¹CHSO₂R² (I; R = Cl, R¹ = H, Me, R² = NMe₂, Ph, CMe₃, morpholino, tolyl; R = Br, R¹ = H, R² = tolyl) react with bicyclic heteroaromatic compounds (quinoxalines, naphthyridines, and 5-azaquinoxalines) according to 2 general pathways: vicarious nucleophilic substitution (VNS) of hydrogen and/or bisannulation. In some cases other competitive reactions are observed Factors governing the direction of these reactions are discussed in terms of the charge distribution in the anionic σ adducts and the reaction conditions. For example reaction of quinoxaline and quinoxaline N-oxide with I (R = Cl, R¹ = H, R² = Ph) gave bisazirinoquinoxaline II and VNS product III resp. In the experiment, the researchers used many compounds, for example, Pyrido[2,3-b]pyrazine (cas: 322-46-3HPLC of Formula: 322-46-3).

Pyrido[2,3-b]pyrazine (cas: 322-46-3) belongs to pyrazine derivatives. Pyrazine is a symmetrical molecule with point group D2h. Pyrazine is less basic than pyridine, pyridazine and pyrimidine. Pyrazines are chemical compounds (technically called “methoxypyrazinesâ€? found in grape skin and stems that are responsible for many “greenâ€?flavors in wine. Levels of pyrazines are dependent on viticultural practices, climate, and grape variety.HPLC of Formula: 322-46-3

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Structure vs. reactivity in quinoxalinecarboxylic acids and esters was written by Gum, Wilson F. Jr.;Joullie, Madeleine M.. And the article was included in Journal of Organic Chemistry in 1965.Formula: C7H8N2O2 This article mentions the following:

In an attempt to establish a correlation between the calculated electron densities in an unperturbed quinoxaline nucleus and the reactivities of its derivatives, the pK_A values of 2-, 2,3-, 6-, 5-, and 2,3-dimethyl-5-quinoxalinecarboxylic acids (I, II, III, IV, V) were measured. The carbonyl frequencies of the corresponding Me and Et esters (VI-XII) were determined by ir spectroscopy and tabulated together with those of Et and Me pyra-zinecarboxylate. Good correlation seemed to exist between pK_A values of the acids I-V and the electron d. calculated by Longuet-Higgins and Coulson (CA 41, 4978b) but only poor correlation with those reported by Basur and Bhattacharya (CA 52, 864i and by Pullman (CA 41, 197b). The split carbonyl bands observed for the esters VI-XII should be ascribed to conformational isomerism rather than to Fermi resonance. Relative pK_A values of I-V were predictable from electron densities of the unsubstituted quinoxaline ring even though the carboxylate anions formed during the determination must perturb the ring densities. The effect is apparently small in relation to the perturbed electron d. caused by the ring N atoms in the unsubstituted quinoxaline nucleus. 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 part of several biologically active polycyclic compounds; examples are quinoxalines, phenazines; and the bio-luminescent natural products pteridines, flavins, and their derivatives. Pyrazine and a variety of alkylpyrazines are flavor and aroma compounds found in baked and roasted goods. Tetramethylpyrazine (also known as ligustrazine) is reported to scavenge superoxide anion and decrease nitric oxide production in human Granulocytes.Formula: C7H8N2O2

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Infrared spectra and intensity enhancements in solutions of hydrogen halides in liquid xenon was written by Goldring, H.;Kwok, J.;Robinson, G. W.. And the article was included in Journal of Chemical Physics in 1965.Recommanded Product: 322-46-3 This article mentions the following:

The intensities and shapes of the vibrational fundamental bands of HCl, HBr, and HI dissolved in liquid Xe at 165°K. are examined While no rotational fine structure was observed, rotational branch maximum were exhibited in all 3 cases. The spectra of the dissolved mols. are different from those of the gaseous mol. in that they exhibit a strong Q branch and probably also O and S branches. This observation should be compared with spectra of H halides in dense gases where a Q branch is prominent, and with spectra of such mols. in solid rare gases where ordinarily a strong Q branch is not produced. The extended selection rules in the liquid are probably caused by anisotropic fields which are capable of mixing J states. In this sense, the rotational motions of the H halides in liquid Xe are not free. The large intensity enhancements, 2.8 for HCl, 3.1 for HBr, and 44 for HI, are inadequately explained on the basis of dielec. polarization effects. Nuclear distortion effects on the intensity enhancements are negligible. Electronic distortion effects must account for the enhancement. A semiquant. description based on the lowering of ionic states of the H halides in the presence of the dielec. medium indicates that for each of the halides studied �/16 of an electron moves from the proton to the halogen when the mol. is dissolved. This is sufficient electronic distortion to account for the intensity enhancement in all 3 mols. This increased ionicity should be manifested not only in ir intensity enhancements but also in permanent dipole moment corrections for dissolved polar mols. The permanent moment corrections may exceed those given by the Onsager dielec. theory. In the experiment, the researchers used many compounds, for example, Pyrido[2,3-b]pyrazine (cas: 322-46-3Recommanded Product: 322-46-3).

Pyrido[2,3-b]pyrazine (cas: 322-46-3) 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. Substituted pyrazines have been found as subunits of multiple synthetically constructed therapeutic agents, as well as several natural products.Recommanded Product: 322-46-3

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electrochemical and spectroscopic investigations of isoniazide and its analogs with ds.DNA at physiological pH: Evaluation of biological activities was written by Arshad, Nasima;Yunus, Uzma;Razzque, Shumaila;Khan, Maliha;Saleem, Samreen;Mirza, Bushra;Rashid, Naghmana. And the article was included in European Journal of Medicinal Chemistry in 2012.Formula: C7H8N2O2 This article mentions the following:

Interaction and binding of isonicotinic acid hydrazide (INH) and its two analogs; pyrazine carboxylic acid hydrazide (PCH) and 2,4-dihydroxy benzoic acid hydrazide (2,4-DHBAH) with DNA has been investigated by UV-spectroscopy and cyclic voltammetry (CV) at physiol. conditions of pH and temperature Exptl. results from both techniques were in good agreement and indicated stronger binding and formation of hydrazides-DNA complexes via intercalation. Among three hydrazides, 2,4-DHBAH showed greater interaction toward DNA at stomach pH (4.7) as evident from its comparatively greater binding constant, {K_b; 2.02 × 10⁴ M^-1 (UV), 3.13 × 10⁴ M^-1 (CV)}. The greater binding site size (n = 3) for 2,4-DHBAH at stomach pH inferred 3:1 binding stoichiometry and possibility of electrostatic interactions or hydrogen bonding along with intercalative mode of interaction between 2,4-DHBAH and DNA. The free energies of hydrazides-DNA complexes indicated the spontaneity of their binding. 2,4-DHBAH has shown promising anti-bacterial activities while anti-oxidant and cytotoxic potentials were exhibited by all three hydrazides. 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

Synthesis of 2-hydroxymethyl-3,5,6-trimethylpyrazine grafted by polyethylene glycol was written by Xia, Cheng-jian;Wang, Song;Zhu, He-sun. And the article was included in Jingxi Huagong in 2004.Name: (3,5,6-Trimethylpyrazin-2-yl)methanol This article mentions the following:

Polyethylene glycol grafted 2-hydroxymethyl-3,5,6-trimethylpyrazine is prepared in 69% yield by condensation of polyethylene glycol dicarboxylic acid and 2-hydroxymethyl-3,5,6-trimethylpyrazine with dicydohexylcarbodiimide (DCCI) as condensating agent. The product is characterized by m.p., FTIR and ₁HNMR; m. p. 45 âˆ?48 °C; IR absorption 1747 cm^-1 (C = O), 1254 cm^-1 (C-O-C); ¹HNMR âˆ?= 1.9 (-CH₃, 3H, s), 2.2 (-CH₃, 6H, s), 4.2 (CH₂-, 2H, s), 3.6 (-OCH₂-, multi-H, s). In the experiment, the researchers used many compounds, for example, (3,5,6-Trimethylpyrazin-2-yl)methanol (cas: 75907-74-3Name: (3,5,6-Trimethylpyrazin-2-yl)methanol).

(3,5,6-Trimethylpyrazin-2-yl)methanol (cas: 75907-74-3) 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. Pyrazines undergo nearly all of the same reactions as pyrimidines, from nucleophilic substitution (SNAr) to palladium-catalyzed cross coupling reactions.Name: (3,5,6-Trimethylpyrazin-2-yl)methanol

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem