Month: January 2023

New Didecyloxyphenylene-Acceptor Alternating Conjugated Copolymers: Synthesis, Properties, and Optoelectronic Device Applications was written by Liu, Cheng-Liang;Tsai, Jung-Hsun;Lee, Wen-Ya;Chen, Wen-Chang;Jenekhe, Samson A.. And the article was included in Macromolecules (Washington, DC, United States) in 2008.COA of Formula: C8H4Br2N2 This article mentions the following:

Seven donor-acceptor copolymers incorporating didecyloxyphenylene (DP) donor and the following acceptors-thieno[3,4-b]pyrazine (TP), 2,1,3-benzothiadiazole (BT), quinoxaline (Q), pyridine (Py), 2,3-dimethyl-5,7-dithien-2-yl-thieno[3,4-b]pyrazine (DTTP), 4,7-dithien-2-yl-2,1,3-benzothiadiazole (DTBT), and 2,3-dimethyl-5,7-dithien-2-yl-quinoxaline (DTQ)-were synthesized by Suzuki coupling polymerization The effects of the acceptor strength and backbone planarity on the optical, electrochem., field-effect charge transport, and photovoltaic properties of the donor-acceptor copolymers were investigated. The optical band gap (eV) of the copolymers showed the trend of DP/TP (1.47) < DP/BT (2.37) < DP/Py (2.76) < DP/Q (2.78) < DP/P (3.15). The DP/TP copolymer had a field-effect hole mobility of 1.89 × 10^-3 cm² V^-1 s^-1. The DP/DTBT and DP/DTQ copolymers showed hole mobilities of 1.92 × 10^-4 and 2.10 × 10^-3 cm² V^-1 s^-1, resp. The strong acceptor strength of TP and coplanar backbone in the DP/TP copolymer resulted in a large intramol. charge transfer, leading to the observed charge transport and optical properties.. These results show that the backbone planarity of the DP/BT and DP/Q copolymers was significantly improved by incorporating thiophene moieties, leading to enhanced charge transport. Photovoltaic cells fabricated from DP/DTBT and DP/DTQ polymers blended with [6,6]-phenyl-C61-butyric acid Me ester (PCBM) showed power conversion efficiencies of 0.40-0.41% under AM 1.5 solar simulator illumination (100 mW/cm²). The results of the present study show that the electronic and optoelectronic properties of dialkoxylphenylene-based donor-acceptor copolymers could be tuned through the acceptor structure and backbone coplanarity. 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. 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 large number of pyrazine derivatives are known for their antitumor, antibiotic, anticonvulsant, antituberculosis, and diuretic activities.COA of Formula: C8H4Br2N2

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

6-Substituted amiloride derivatives as inhibitors of the urokinase-type plasminogen activator for use in metastatic disease was written by Buckley, Benjamin J.;Majed, Hiwa;Aboelela, Ashraf;Minaei, Elahe;Jiang, Longguang;Fildes, Karen;Cheung, Chen-Yi;Johnson, Darren;Bachovchin, Daniel;Cook, Gregory M.;Huang, Mingdong;Ranson, Marie;Kelso, Michael J.. And the article was included in Bioorganic & Medicinal Chemistry Letters in 2019.Recommanded Product: Methyl 3,5-diamino-6-chloropyrazine-2-carboxylate This article mentions the following:

Aryldiaminopyrazinecarbonyl guanidines I (R = Ph, 4-MeSC₆H₄, 4-F₃CC₆H₄, 5-pyrimidinyl, 2,4-dimethoxy-5-pyrimidinyl, 2-methoxy-5-pyrimidinyl, 2,6-dimethoxy-3-pyridinyl, 2-thienyl, 2-furanyl, 3-furanyl, 1-methyl-4-pyrazolyl, 2-benzothienyl, 5-R¹-2-benzofuranyl, 6-methoxy-2-benzofuranyl, 2,3-dihydro-5-benzofuranyl; R¹ = H, Me, MeO, F, Cl, Br, NC) were prepared as analogs of the potassium ion-sparing diuretic amiloride for the inhibition of urokinase-type plasminogen activator (uPA) and for inhibiting tumor metastasis. The structures of four aryldiaminopyrazinecarbonyl guanidines bound to uPA were determined by X-ray crystallog.; the improved inhibition of uPA by amiloride analogs likely arise from increased occupancy of uPA’s S1β subsite by the aryl substituents. I (R = 2-benzofuranyl, 2-methoxy-5-pyrimidinyl) were selective for uPA over related trypsin-like serine proteases and did not show diuretic or anti-kaliuretic effects in rats. I (R = 2-benzofuranyl) inhibited tumor metastasis in a murine xenograft lung cancer model. In the experiment, the researchers used many compounds, for example, Methyl 3,5-diamino-6-chloropyrazine-2-carboxylate (cas: 1458-01-1Recommanded Product: 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. 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.Recommanded Product: Methyl 3,5-diamino-6-chloropyrazine-2-carboxylate

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Oxidation of hydroxymethylpyrazines and hydroxylated phenyl compounds in a gas chromatography inlet was written by Bohman, B.;Flematti, G. R.. And the article was included in Analytical Methods in 2015.Application of 75907-74-3 This article mentions the following:

Large proportions of aldehydes were formed when hydroxymethylpyrazines, and benzyl- and cinnamyl alcs. were analyzed by gas chromatog.-mass spectrometry using a heated inlet with a previously used glass inlet liner. To avoid false reporting of non-natural compounds, any identification of aldehydes potentially formed in a GC inlet requires verification. In the experiment, the researchers used many compounds, for example, (3,5,6-Trimethylpyrazin-2-yl)methanol (cas: 75907-74-3Application of 75907-74-3).

(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 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.Application of 75907-74-3

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Novel transformation of 1,2,4-triazines into pyrazine derivatives was written by Alekseev, S. G.;Charushin, V. N.;Chupakhin, O. N.. And the article was included in Khimiya Geterotsiklicheskikh Soedinenii in 1987.Reference of 322-46-3 This article mentions the following:

Pyrazines I (X = e.g. CH, N) were prepared by the reaction of aromatic o-diamines with triazinium salt II and subsequent elimination of morpholinoamidrazone from the intermediate III. In the experiment, the researchers used many compounds, for example, Pyrido[2,3-b]pyrazine (cas: 322-46-3Reference 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. 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.Reference of 322-46-3

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Mononuclear and polynuclear halide and nitrate Cu(II) compounds with 1,4,5-triazanaphthalene as a ligand: Characterization, magnetism and X-ray structures was written by van Albada, Gerard A.;van der Horst, Maarten G.;Fu, Wen Tian;Roubeau, Olivier;Mutikainen, Ilpo;Turpeinen, Urho;Reedijk, Jan. And the article was included in Inorganica Chimica Acta in 2009.Recommanded Product: Pyrido[2,3-b]pyrazine This article mentions the following:

Using the ligand 1,4,5-triazanaphthalene (abbreviated as tan) in reaction with Cu(II) salts, three mononuclear compounds, Cu(tan)₂Cl₂ (1), Cu(tan)₂Br₂ (3), Cu(tan)₂(NO₃)₂ (5) and three polynuclear compounds, [Cu(tan)Cl₂]_n (2), [Cu(tan)Br₂]_n (4), [Cu(tan)(NO₃)₂]_n (6) were prepared and characterized by UV-visible, EPR, FTIR and Far-FTIR spectroscopies. The crystal structures of compounds 1, 3, 5 and 6 are reported, as well as that of the dioxane adduct of compound 4, [Cu(tan)Br₂(C₄H₈O₂)](C₄H₈O₂) (4A). The structure of 2 was solved by x-ray powder diffraction. The coordination geometry around the Cu(II) atoms is tetrahedral for (1) and (3), square-pyramidal for (4A) and distorted octahedral for (5) and (6). Magnetic susceptibility measurements on the polynuclear compounds revealed weak antiferromagnetic interactions between the Cu(II) atoms with interaction constants (J) of J = -9.1 and -10.5 cm^-1, for 4 and 6, resp. For compound 2 two options for possible interactions were considered, with interaction constants which vary for J _rung -22.0 to -13.5 cm^-1 and J _rail -19.6 to -17.0 cm^-1. These figures are discussed in the light of relevant structural parameters and literature. In the experiment, the researchers used many compounds, for example, Pyrido[2,3-b]pyrazine (cas: 322-46-3Recommanded Product: Pyrido[2,3-b]pyrazine).

Pyrido[2,3-b]pyrazine (cas: 322-46-3) 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. A number of pyrazine-based derivatives were used as dyes or fluorescent probes.Recommanded Product: Pyrido[2,3-b]pyrazine

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Continuous flow as an enabling technology: a fast and versatile entry to functionalized glyoxal derivatives was written by Lima, Fabio;Meisenbach, Mark;Schenkel, Berthold;Sedelmeier, Joerg. And the article was included in Organic & Biomolecular Chemistry in 2021.Application In Synthesis of Ethyl pyrazine-2-carboxylate This article mentions the following:

Two complementary strategies employing organolithium chem. for the synthesis of glyoxal derivatives RC(O)R¹R² (R = methoxymethyl, 3,5-difluorophenyl, pyridin-2-yl, quinolin-6-yl, etc.; R¹ = Cl, OEt, H; R² = Cl, OEt, 3-chlorophenyl) were reported. Micro-mixer technol. allows for the generation of unstable organometallic intermediates and their instantaneous in-line quenching with esters as electrophiles RC(O)OEt. Selective mono-addition was observed via putative stabilized tetrahedral intermediates. Advantages offered by flow chem. technologies facilitate direct and efficient access to masked 1,2-dicarbonyl compounds while mitigating undesired byproduct formation. These two approaches enable the production of advanced and valuable synthetic building blocks for heterocyclic chem. with throughputs of grams per min. In the experiment, the researchers used many compounds, for example, Ethyl pyrazine-2-carboxylate (cas: 6924-68-1Application In Synthesis of Ethyl pyrazine-2-carboxylate).

Ethyl pyrazine-2-carboxylate (cas: 6924-68-1) 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. Substituted pyrazines have been found as subunits of multiple synthetically constructed therapeutic agents, as well as several natural products.Application In Synthesis of Ethyl pyrazine-2-carboxylate

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Band-gap engineering of donor-acceptor-substituted π-conjugated polymers was written by Van Mullekom, H. A. M.;Vekemans, J. A. J. M.;Meijer, E. W.. And the article was included in Chemistry – A European Journal in 1998.Recommanded Product: 5,8-Dibromoquinoxaline This article mentions the following:

Three series of alternating donor-acceptor-substituted co-oligomers (with different chain lengths) have been prepared by application of the Pd-catalyzed Stille coupling methodol. They contain pyrrole or thiophene as the electron-rich unit and quinoxaline or 2,1,3-benzothiadiazole as the electron-deficient unit. The trimethylstannyl group is always located on the electron-rich unit, whereas the bromo substituent is always located on the electron-deficient one. The tBoc-protecting group is used in the synthesis of the pyrrole-containing oligomers. The incremental bathochromic shift of λ_max upon chain elongation of the three series of oligomers is less than that of the homo-oligomers of thiophene and pyrrole; this decrease is caused by a diminished dispersion of the LUMO level upon chain elongation. This conclusion was drawn after comparing the oxidation and reduction behavior of the thiophene/benzothiadiazole co-oligomers with that of thiophene oligomers. The incremental bathochromic shift is similar for all three series of oligomers and is used as a tool in the band-gap engineering of donor-acceptor-substituted π-conjugated polymers. In the experiment, the researchers used many compounds, for example, 5,8-Dibromoquinoxaline (cas: 148231-12-3Recommanded Product: 5,8-Dibromoquinoxaline).

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. 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: 5,8-Dibromoquinoxaline

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electron affinities of aza-substituted polycyclic aromatic hydrocarbons was written by Dillow, Glen W.;Kebarle, P.. And the article was included in Canadian Journal of Chemistry in 1989.Reference of 322-46-3 This article mentions the following:

Electron affinities (EA) for aza-substituted polycyclic aromatics, e.g., quinazoline, were determined from measurements of electron transfer equilibrium in the dilute gas phase with a pulsed electron high pressure mass spectrometer. Solvation energies of the corresponding radical anions in acetonitrile and DMF are derived from the gas-phase data and literature on electron reduction potentials in solution An observed linear relation between the electron affinities and the reduction potentials allows estimates of electron affinities to be made for 12 aza compounds whose EA’s are too low to be measured with the present method. In the experiment, the researchers used many compounds, for example, Pyrido[2,3-b]pyrazine (cas: 322-46-3Reference 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. 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.Reference of 322-46-3

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Instances of nonelectrolyte solvation leading to less pronounced rate enhancements of ester hydrolyses in dipolar aprotic solvents: the possibility of hydrolysis via conjugate base formation in the case of ethyl indole-2-carboxylate and methyl 4-pyridylacetate was written by Rao, G. Venkoba;Balakrishnan, M.;Venkatasubramanian, N.;Subramanian, P. V.;Subramanian, V.. And the article was included in Journal of the Chemical Society, Perkin Transactions 2: Physical Organic Chemistry (1972-1999) in 1978.Computed Properties of C7H8N2O2 This article mentions the following:

The kinetics of alk. hydrolysis of the heterocyclic esters I (RR¹ = benzo, X = NH; R = R¹ = H, X = O, S), II (R = CH₂CO₂Et, CO₂Et, R¹ = R² = H; R = R¹ = H, R² = CH₂CO₂Me, CO₂Et; R = R² = H, R¹ = CO₂Et, CH₂CO₂Et), III, BzOEt, and PhCH₂CO₂Et were studied in binary solvent mixtures of Me₂SO-H₂O and EtOH-H₂O. The rate data for I (RR¹ = benzo, X = NH) and II (R = R¹ = H, R² = CH₂CO₂Me) indicated the possibility of an E1cb route for their hydrolysis. The hydrolysis of heterocyclic esters constitute a unique case in which the rate enhancements of ester saponification on transfer from protic to dipolar aprotic solvents are governed by the solvation of the nonelectrolyte (ester) mol. by Me₂SO, a factor hitherto relegated to the background. In the experiment, the researchers used many compounds, for example, Ethyl pyrazine-2-carboxylate (cas: 6924-68-1Computed Properties of C7H8N2O2).

Ethyl pyrazine-2-carboxylate (cas: 6924-68-1) 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. 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.Computed Properties of C7H8N2O2

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Identification, characterization, synthesis and quantification of related impurities of liguzinediol was written by Cheng, Dong;Zhou, Ying;Li, Wei;Shan, Chen-Xiao;Chai, Chuan;Cui, Xiao-Bing;Kang, Bi;Wang, Tian-Lin;Wen, Hong-Mei. And the article was included in Journal of Chromatographic Science in 2015.SDS of cas: 75907-74-3 This article mentions the following:

An HPLC method was employed to create an impurity profile for liguzinediol as an active pharmaceutical ingredient (API), which resulted in the identification of two related impurities. Therefore, in order to improve the quality control of the liguzinediol-API, we identified and then developed a method for quantifying the two impurities (impurity-1 and impurity-2) by LC-TOF-MS-MS and then chem. synthesized them for further studies. Based on spectral data from IR, MS, 1H and 13C NMR, the structures of impurity-1 and impurity-2 were characterized as 2-hydroxymethyl-3,6-dimethylpyrazine and 2-hydroxymethyl-3,5,6-trimethylpyrazine, resp. We further validated the method according to the International Conference on Harmonization guidelines to demonstrate the sensitivity, precision, linearity, accuracy and stability of the method described. In addition, the potential mechanisms underlying formation of impurity-1 and impurity-2 in the liguzinediol-API are discussed in detail. In the experiment, the researchers used many compounds, for example, (3,5,6-Trimethylpyrazin-2-yl)methanol (cas: 75907-74-3SDS of cas: 75907-74-3).

(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. 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.SDS of cas: 75907-74-3

Referemce:
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem