Category: Pyrazines

Whole-Molecule Calculation of Log P Based on Molar Volume, Hydrogen Bonds, and Simulated ¹³C NMR Spectra was written by Schnackenberg, Laura K.;Beger, Richard D.. And the article was included in Journal of Chemical Information and Modeling in 2005.Product Details of 6924-68-1 This article mentions the following:

The prediction of Log P is usually accomplished using either substructure or whole-mol. approaches. However, these methods are complicated, and previous whole-mol. approaches have not been successful for the prediction of Log P in very complex mols. The observed chem. shifts in NMR spectroscopy are related to the electrostatics at the nucleus, which are influenced by solute-solvent interactions. The different solvation effects on a mol. by either water or methanol have a strong effect on the NMR chem. shift value. Therefore, the chem. shift values observed in an aqueous and organic solvent should correlate to Log P. This paper develops a rapid, objective model of Log P based on molar volume, hydrogen bonds, and differences in calculated ¹³C NMR chem. shifts for a diverse set of compounds A partial least squares (PLS) model of Log P built on the sum of carbon chem. shift differences in water and methanol, molar volume, number of hydrogen bond donors and acceptors in 162 diverse compounds gave an r² value of 0.88. The average r² for 10 training models of Log P made from 90% of the data was 0.87±0.01. The average q² for 10 leave-10%-out cross-validation test sets was 0.87±0.05. In the experiment, the researchers used many compounds, for example, Ethyl pyrazine-2-carboxylate (cas: 6924-68-1Product Details of 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. A number of pyrazine-based derivatives were used as dyes or fluorescent probes.Product Details of 6924-68-1

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

D-A-π-A featured sensitizers by modification of auxiliary acceptor for preventing “trade-off” effect was written by Zhu, Haibo;Liu, Bo;Liu, Jingchuan;Zhang, Weiwei;Zhu, Wei-Hong. And the article was included in Journal of Materials Chemistry C: Materials for Optical and Electronic Devices in 2015.COA of Formula: C8H4Br2N2 This article mentions the following:

Four D-A-π-A motif organic sensitizers (IQ9, IQ10, IQ11, and IQ12) in the absence or presence of thiophene substituents grafted onto the auxiliary acceptor of a quinoxaline unit were developed for dye sensitized solar cells (DSSCsa). Upon changing the π-linker from benzene to thiophene, the photocurrent (J_sc) of IQ10 increases around 2-fold, and the photovoltage (V_oc) decreases by 52 mV compared to that of IQ9. It is attributed to the fact that compared with the benzene linker, the thiophene conjugated bridge in dye IQ10 induces a small twist in the mol. planarity, thus resulting in the high light-harvesting capability (beneficial to J_sc) and high charge recombination (unbeneficial to V_oc). To prevent this trade-off effect between photocurrent and photovoltage, the building block of 2,3-dithienylquinoxaline as an auxiliary unit is specifically incorporated, which brings forth several advantages such as distinctly extending the light-harvesting region, increasing molar absorption coefficients, and blocking the dye self-aggregation to reduce charge recombination. Remarkably, dye IQ12 exhibits a beneficial balance between J_sc (17.97 mA cm^-2) and V_oc (715 mV), along with a promising photovoltaic efficiency of 8.76%, much better than the corresponding dyes IQ9 (2.91%), IQ10 (7.75%) and IQ11 (6.56%). As demonstrated, the two twisted thiophene groups grafted onto the quinoxaline unit facilitate the resulting compact sensitizer layer to effectively overcome the charge recombination drawbacks in V_oc arising from the thiophene π-bridge linker, providing a rational mol. engineering to pursue the synergistic enhancement in the photocurrent and photovoltage for highly efficient organic sensitizers. In the experiment, the researchers used many compounds, for example, 5,8-Dibromoquinoxaline (cas: 148231-12-3COA of Formula: C8H4Br2N2).

5,8-Dibromoquinoxaline (cas: 148231-12-3) 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. A number of pyrazine-based derivatives were used as dyes or fluorescent probes.COA of Formula: C8H4Br2N2

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthesis, characterization and molecular structures of some tetraosmium carbonyl clusters containing pyridine or phenanthroline type ligands was written by Choi, Ya-Yin;Wong, Wing-Tak. And the article was included in Journal of Organometallic Chemistry in 1999.COA of Formula: C7H5N3 This article mentions the following:

The reactions of activated tetraosmium carbonyl cluster [Os₄(μ-H)₄(CO)₁₁(NCMe)] (1) with monopyridyl ligands give new clusters [Os₄(μ-H)₄(CO)₁₁,(pyp)] (3) and [Os₄(μ-H)₄ (CO)₁₁(pya)] (4) (pyp = pyrido[2,3-b]pyrazine, pya = 4-pyridinecarboxaldehyde). Similarly, the reactions of [Os₄(μ-H)₄(CO)₁₀(NCMe)₂] (2) with bipyridyl or phenanthroline type ligands afford [Os₄(μ-H)₄(CO)₁₀(bpy)] (5), [Os₄(μ-H)₄ (CO)₁₀(4,4′-diphenyl-2,3-bipyridine)] (6), [Os₄(μ-H)₄(CO)₁₀(phen)] (7), [Os₄(μ-H)₄(CO)₁₀(2,9-dimethyl-4,4′-diphenyl-1,10-phenanthroline)] (8), and [Os₄(μ-H)₄(CO)₁₀(dipyrido[3,2-a:2′,3′-c]phenazine)] (9), which exhibit interesting ring conformations. Treatment of 2 with the N-P mixed donor ligand diphenyl-2-pyridylphosphine (dppy) gives a novel bridging cluster [Os₄(μ-H)₄(CO)₁₀(dppy)] (10). In the experiment, the researchers used many compounds, for example, Pyrido[2,3-b]pyrazine (cas: 322-46-3COA of Formula: C7H5N3).

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). 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.COA of Formula: C7H5N3

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Time-resolved electron paramagnetic resonance investigation of photochemical reactions. Hydrogen abstraction in azaaromatics and carbonyls was written by Yamauchi, Seigo;Hirota, Noboru. And the article was included in Journal of Physical Chemistry in 1984.Related Products of 322-46-3 This article mentions the following:

Transient ESR spectra were observed for the intermediate radicals in the photoinduced H abstractions of azaarom. mols. and carbonyls in Me₂CHOH. Temperature dependence was examined at -10 to -90°. The intermediate radicals are assigned from the spectra with partially resolved hyperfine structures. The precursory excited states for the reactions are determined from the signal polarities, and their properties are discussed in terms of the possible CIDEP mechanisms. The reactions occur from the T₁(nπ^*) states with neg. D values or the T₁(ππ^*) states with pos. D in the cases of azaaroms. In aromatic carbonyls the reactions occur from the T₁(nπ^*) or T₂(nπ^*) states with neg. D values, while in aliphatic carbonyls, from the T₁(nπ^*) states with pos. D values. In the experiment, the researchers used many compounds, for example, Pyrido[2,3-b]pyrazine (cas: 322-46-3Related Products of 322-46-3).

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. Substituted pyrazines have been found as subunits of multiple synthetically constructed therapeutic agents, as well as several natural products.Related Products of 322-46-3

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Toward a Rational Design of Poly(2,7-Carbazole) Derivatives for Solar Cells was written by Blouin, Nicolas;Michaud, Alexandre;Gendron, David;Wakim, Salem;Blair, Emily;Neagu-Plesu, Rodica;Belletete, Michel;Durocher, Gilles;Tao, Ye;Leclerc, Mario. And the article was included in Journal of the American Chemical Society in 2008.Category: pyrazines This article mentions the following:

From theor. models and calculations, several alternating polymeric structures were studied to develop optimized poly(2,7-carbazole) derivatives for solar cell applications. Selected low band gap alternating copolymers were obtained via a Suzuki coupling reaction. A good correlation between DFT theor. calculations performed on model compounds and the exptl. HOMO, LUMO, and band gap energies of the corresponding polymers was obtained. This study reveals that the alternating copolymer HOMO energy level is mainly fixed by the carbazole moiety, whereas the LUMO energy level is mainly related to the nature of the electron-withdrawing comonomer. However, solar cell performances are not solely driven by the energy levels of the materials. Clearly, the mol. weight and the overall organization of the polymers are other important key parameters to consider when developing new polymers for solar cells. Preliminary measurements revealed hole mobilities of ∼1 × 10^-3 cm²/V-s and a power conversion efficiency (PCE) up to 3.6%. Further improvements are anticipated through a rational design of new sym. low band gap poly(2,7-carbazole) derivatives In the experiment, the researchers used many compounds, for example, 5,8-Dibromoquinoxaline (cas: 148231-12-3Category: pyrazines).

5,8-Dibromoquinoxaline (cas: 148231-12-3) 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. Pyrazine-based skeletons were incorporated into agents targeting a range of ailments. Many derivatives were synthesized and evaluated as potential cancer treatments.Category: pyrazines

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthesis of tetramethylpyrazine metabolites was written by Liu, Xinyong;Ge, Weiying;Xu, Lijun;Zhang, Junren;Wang, Haiyan;Pan, Shuju. And the article was included in Shandong Yike Daxue Xuebao in 1997.COA of Formula: C8H12N2O This article mentions the following:

2-Acetoxylmethyl-3,5,6-trimethylpyrazine, 3,5,6-trimethylpyrazine methanol and 3,5,6-trimethylpyrazine formic acid were prepared from tetramethylpyrazine oxidation The alc. and the acid were tested active in lowering both cholesterol and LDL level in rabbit. In the experiment, the researchers used many compounds, for example, (3,5,6-Trimethylpyrazin-2-yl)methanol (cas: 75907-74-3COA of Formula: C8H12N2O).

(3,5,6-Trimethylpyrazin-2-yl)methanol (cas: 75907-74-3) 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 undergo nearly all of the same reactions as pyrimidines, from nucleophilic substitution (SNAr) to palladium-catalyzed cross coupling reactions.COA of Formula: C8H12N2O

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Intramolecular Diels-Alder reaction of pyrazines with an alkenyl side chain was written by Chen, Bin;Yang, Chu-Yao;Ye, De-Yong. And the article was included in Tetrahedron Letters in 1996.Electric Literature of C8H12N2O This article mentions the following:

Intramol. Diels-Alder reaction of a series of pyrazines bearing a 5-membered-ω-alkene side chain, I (X = O, SO, SO₂, S), in refluxing trifluoroacetic acid led to the formation of bridged tricyclic compounds II. These cycloadducts underwent retro Diels-Alder reaction in refluxing nitrobenzene to give the original pyrazines. 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 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.Electric Literature of C8H12N2O

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Design, synthesis, and biological activities of novel Ligustrazine derivatives was written by Cheng, Xian-Chao;Liu, Xin-Yong;Xu, Wen-Fang;Guo, Xiu-Li;Ou, Yang. And the article was included in Bioorganic & Medicinal Chemistry in 2007.Computed Properties of C8H12N2O This article mentions the following:

A series of novel Ligustrazine derivatives was designed, synthesized, and assayed for their protective effects on damaged ECV-304 cells and antiplatelet aggregation activities. The results showed that most Ligustrazine derivatives exhibited lower EC₅₀ values for protective effects on the ECV-304 cells damaged by hydrogen peroxide in comparison with Ligustrazine. And some Ligustrazine derivatives presented better antiplatelet aggregation activities than Ligustrazine. The derivatives containing the bisphenylmethyl pharmacophore (7a-c) exhibited highest potency. Compound 7a displayed most potential protective effects on the ECV-304 cells damaged by hydrogen peroxide, and compound 7c was found to be the most active antiplatelet aggregation agent. Structure-activity relationships were briefly discussed. In the experiment, the researchers used many compounds, for example, (3,5,6-Trimethylpyrazin-2-yl)methanol (cas: 75907-74-3Computed Properties of C8H12N2O).

(3,5,6-Trimethylpyrazin-2-yl)methanol (cas: 75907-74-3) 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. Pyrazine-based skeletons were incorporated into agents targeting a range of ailments. Many derivatives were synthesized and evaluated as potential cancer treatments.Computed Properties of C8H12N2O

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Palladium-catalyzed difluoromethylthiolation of heteroaryl bromides, iodides, triflates and aryl iodides was written by Wu, Jiang;Liu, Yafei;Lu, Changhui;Shen, Qilong. And the article was included in Chemical Science in 2016.Computed Properties of C4H2BrClN2 This article mentions the following:

Palladium-catalyzed difluoromethylthiolation of heteroaryl halides and triflates under mild conditions was described. A vast range of heteroaryl halides such as pyridyl, quinolinyl, benzothiazolyl, thiophenyl, carbazolyl and pyrazolyl halides could be difluoromethylthiolated efficiently, thus providing medicinal chemists with new tools for their search of new led compounds for drug discovery. Likewise, aryl iodides were difluoromethylthiolated in high yields under a modified reaction condition. In the experiment, the researchers used many compounds, for example, 2-Bromo-5-chloropyrazine (cas: 912773-21-8Computed Properties of C4H2BrClN2).

2-Bromo-5-chloropyrazine (cas: 912773-21-8) 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. Pyrazine-based skeletons were incorporated into agents targeting a range of ailments. Many derivatives were synthesized and evaluated as potential cancer treatments.Computed Properties of C4H2BrClN2

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electronic structure of small band gap oligomers based on cyclopentadithiophenes and acceptor units was written by Karsten, Bram P.;Bijleveld, Johannes C.;Viani, Lucas;Cornil, Jerome;Gierschner, Johannes;Janssen, Rene A. J.. And the article was included in Journal of Materials Chemistry in 2009.Related Products of 148231-12-3 This article mentions the following:

A combined exptl. and theor. study was carried out on a series of well-defined small band gap oligomers. The cyclopentadithiophene oligomers were prepared by Suzuki coupling of thiopheneboronic esters and dibromophenylquinoxaline compounds These oligomers comprise two terminal electron-rich cyclopentadithiophene units connected to six different electron deficient aromatic rings that allow tuning the optical band gap from 1.4 to 2.0 eV. The optical absorption of the ground state, triplet excited state, and radical cation was studied. The optical band gap correlates with the electrochem. oxidation and reduction potential and is further supported by quantum-chem. calculations at the d. functional theory (DFT) level. The optical absorption of the radical cations shows only little variations among the different oligomers, suggesting that the charge is mainly localized on the donor moieties. Triplet energy levels are generally low (<1.2 eV) and the singlet-triplet splitting remains significant when going to smaller band gaps. In the experiment, the researchers used many compounds, for example, 5,8-Dibromoquinoxaline (cas: 148231-12-3Related Products of 148231-12-3).

5,8-Dibromoquinoxaline (cas: 148231-12-3) 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.Related Products of 148231-12-3

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem