Month: December 2021

Safety of Pyrazine-2-carboxylic acid. Authors Yang, YJ; Wang, K; Yang, Y; Lai, FF; Chen, XG; Xiao, ZY in TAYLOR & FRANCIS LTD published article about in [Yang, Ya-Jun; Wang, Ke; Yang, Ying; Xiao, Zhi-Yan] Chinese Acad Med Sci & Peking Union Med Coll, Inst Mat Med, Beijing Key Lab Active Subst Discovery & Druggabi, Beijing 100050, Peoples R China; [Lai, Fang-Fang; Chen, Xiao-Guang] Chinese Acad Med Sci & Peking Union Med Coll, Inst Mat Med, State Key Lab Bioact Subst & Funct Nat Med, Beijing 100050, Peoples R China in 2021, Cited 21. The Name is Pyrazine-2-carboxylic acid. Through research, I have a further understanding and discovery of 98-97-5

Based on the interaction modes of the natural 20S proteasome inhibitors TMC-95A, we have previously discovered a dipeptide 1. To explore the SAR around compound 1, we designed and synthesized a series of dipeptides (8-38) with a fragment-based strategy. Among them, nine compounds showed significant inhibitory activities against the chymotrypsin-like activity of human 20S proteasome with IC50 values at the submicromolar level, which were comparable or even superior to the parent compound 1. Meanwhile, they displayed no significant inhibition against trypsin-like and caspase-like activities of 20S proteasome. The results suggested the feasibility to design dipeptides as novel and potent 20S proteasome inhibitors.

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Reference:
Patent; Chevron Research Company; US4732894; (1988); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Category: Pyrazines. Wang, Y; Chen, FF; Hu, XS; Zhao, R; Chi, YX; Jin, J in [Wang Yan; Chen Fei-Fei; Hu Xiao-Shuang; Zhao Ran; Chi Yu-Xian; Jin Jing] Liaoning Normal Univ, Sch Chem & Chem Engn, Dalian 116029, Liaoning, Peoples R China published Syntheses, Crystal Structures and Luminescent Properties of Ag-Ln Coordination Polymers in 2019, Cited 42. The Name is Pyrazine-2-carboxylic acid. Through research, I have a further understanding and discovery of 98-97-5.

Using pyrazine-2-carboxylic acid (2-Hpzc), 3,5-pyridinedicarboxylic acid (3,5-H(2)PDA) and oxalic acid (H(2)ox) as ligands, nine Ag-Ln coordination polymers are synthesized by hydrothermal methods: {[LnAg(2-pzc)(2)(ox)]center dot H(2)ox} (Ln=Pr (1), Nd (2), Sm (3), Eu (4)), [LnAg(3,5-PDA)(ox)(H2O)](n), (Ln=Pr (5), Nd (6)), [LnAg(3,5-PDA)(3,5-HPDA)(ox)(0.5)(H2O)(2)](n) (Ln=Sm (7), Dy (8), Ho (9)). All of them possess the 3D network structure, i.e., coordination polymers 1 similar to 4 are isomorphic and connected by 2-pzc(-) and ox(2-), while coordination polymers 5 similar to 9 use 3,5-PDA(2-) and ox(2-) as bridging ligands. Photophysical properties of these coordination polymers are studied, and they show characteristic emissions of corresponding Ln(III) ions which should be attributed to the sensitization of the Agligand section (d-block). In addition, under the co-action of crystal field and 4d orbits of Ag(I) ion, the 4f orbits of Ln(III) ions are tuned and cause obvious shift of partial energy levels, which present shifts of the corresponding NIR emission bands and can be corroborated in their UV-Vis-NIR absorption spectra. CCDC: 1817276, 1; 1817247, 2; 1817248, 3; 1817249, 4; 1817251, 5; 1817255, 6; 1817269, 7; 1817280, 8; 1817285, 9.

Category: Pyrazines. Bye, fridends, I hope you can learn more about C5H4N2O2, If you have any questions, you can browse other blog as well. See you lster.

Reference:
Patent; Chevron Research Company; US4732894; (1988); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

SDS of cas: 98-97-5. Lei, JC; Ruan, YX; Luo, S; Yang, JS in [Lei, Jin-Cai; Ruan, Yu-Xiong; Luo, Sheng; Yang, Jin-Song] Sichuan Univ, West China Hosp, Key Lab Drug Targeting & Drug Delivery Syst, Sichuan Engn Lab Plant Sourced Drug,Educ Minist, Chengdu 610041, Sichuan, Peoples R China; [Lei, Jin-Cai; Ruan, Yu-Xiong; Luo, Sheng; Yang, Jin-Song] Sichuan Univ, West China Hosp, West China Sch Pharm, Sichuan Res Ctr Drug Precis Ind Technol, Chengdu 610041, Sichuan, Peoples R China; [Lei, Jin-Cai; Ruan, Yu-Xiong; Luo, Sheng; Yang, Jin-Song] Sichuan Univ, West China Hosp, State Key Lab Biotherapy, Chengdu 610041, Sichuan, Peoples R China published Stereodirecting Effect of C3-Ester Groups on the Glycosylation Stereochemistry of L-Rhamnopyranose Thioglycoside Donors: Stereoselective Synthesis of alpha- and beta-L-Rhamnopyranosides in 2019, Cited 47. The Name is Pyrazine-2-carboxylic acid. Through research, I have a further understanding and discovery of 98-97-5.

The tuning effect of C3-ester groups on the glycosylation stereochemistry of L-rhamnopyranose (L-Rha) ethyl thioglycoside donors is described. On one hand, the L-Rha thioglycoside donors carrying 3-O-arylcarbonyl or levulinoyl group undergo highly alpha-selective glycosylation to afford a wide variety of alpha-L-rhamnoside products in high chemical yields. On the other hand, the glycosylation of the 3-O-4-nitropicoloyl and 2-pyrazinecarbonyl group substituted L-Rha thioglycosides displays beta-stereoselectivity. Only or predominant beta anomeric products are obtained when these L-Rha donors couple with the primary or reactive secondary acceptors, while the beta-selectivity may decrease significantly when these donors react with less reactive secondary alcohols. The synthetic utility of the newly developed alpha- and beta-directing L-Rha donors 1h and 1e has been demonstrated by the efficient synthesis of a structurally unique trisaccharide 9, which is derived from the cell wall polysaccharide of Sphaerotilus natans.

Welcome to talk about 98-97-5, If you have any questions, you can contact Lei, JC; Ruan, YX; Luo, S; Yang, JS or send Email.. SDS of cas: 98-97-5

Reference:
Patent; Chevron Research Company; US4732894; (1988); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

An article Synthesis and catalytic applications of Ru and Ir complexes containing N,O-chelating ligand WOS:000575166800007 published article about TRANSFER HYDROGENATION; ALPHA-ALKYLATION; RUTHENIUM(II) COMPLEXES; PRIMARY ALCOHOLS; KETONES; IRIDIUM; DEHYDROGENATION; REACTIVITY; SECONDARY; BEARING in [Pakyapan, Bilge; Kavukcu, Serdar Batikan; Turkmen, Hayati] Univ Ege, Fac Sci, Dept Chem, TR-35100 Izmir, Turkey; [Sahin, Zarife Sibel] Univ Sinop, Sci & Technol Res Applicat & Res Ctr, Sinop, Turkey in 2020, Cited 44. Safety of Pyrazine-2-carboxylic acid. The Name is Pyrazine-2-carboxylic acid. Through research, I have a further understanding and discovery of 98-97-5

A series of monometallic complexes (Ru1-3, Ir-1(-3)) which have N,O-chelating ligand (pyrazine-2carboxylate (1), pyridine-2-carboxylate (2), quinoline carboxylate(3) and bimetallic complexes (Ru-4,Ru-5, Ir-4(,5)) bridged by pyrazine-2,3- dicarboxylate (4) and imidazole-4,5-dicarboxylate(5) were synthesized and characterized by H-1-, C-13 NMR, FT-IR, and elemental analysis. The crystal structure of Ir-2 was determined by X-ray crystallography. The complexes (Ru1-5, Ir1-5) were applied to investigate the electronic and steric effect of ligand in their catalytic activities in transfer hydrogenation and alpha(alpha)-alkylation reaction of ketones with alcohols. The activities of iridium complexes (Ir1-5) were much more efficient than ruthenium complexes (Ru1-5). The highest activity for both reactions was observed for the complex (Ir2 ) with pyridine-2-carboxylate. The Ir hydride species was monitored for both reactions. (C) 2020 Elsevier B.V. All rights reserved.

Welcome to talk about 98-97-5, If you have any questions, you can contact Pakyapan, B; Kavukcu, SB; Sahin, ZS; Turkmen, H or send Email.. Safety of Pyrazine-2-carboxylic acid

Reference:
Patent; Chevron Research Company; US4732894; (1988); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Authors Pakyapan, B; Kavukcu, SB; Sahin, ZS; Turkmen, H in ELSEVIER SCIENCE SA published article about TRANSFER HYDROGENATION; ALPHA-ALKYLATION; RUTHENIUM(II) COMPLEXES; PRIMARY ALCOHOLS; KETONES; IRIDIUM; DEHYDROGENATION; REACTIVITY; SECONDARY; BEARING in [Pakyapan, Bilge; Kavukcu, Serdar Batikan; Turkmen, Hayati] Univ Ege, Fac Sci, Dept Chem, TR-35100 Izmir, Turkey; [Sahin, Zarife Sibel] Univ Sinop, Sci & Technol Res Applicat & Res Ctr, Sinop, Turkey in 2020, Cited 44. Quality Control of Pyrazine-2-carboxylic acid. The Name is Pyrazine-2-carboxylic acid. Through research, I have a further understanding and discovery of 98-97-5

A series of monometallic complexes (Ru1-3, Ir-1(-3)) which have N,O-chelating ligand (pyrazine-2carboxylate (1), pyridine-2-carboxylate (2), quinoline carboxylate(3) and bimetallic complexes (Ru-4,Ru-5, Ir-4(,5)) bridged by pyrazine-2,3- dicarboxylate (4) and imidazole-4,5-dicarboxylate(5) were synthesized and characterized by H-1-, C-13 NMR, FT-IR, and elemental analysis. The crystal structure of Ir-2 was determined by X-ray crystallography. The complexes (Ru1-5, Ir1-5) were applied to investigate the electronic and steric effect of ligand in their catalytic activities in transfer hydrogenation and alpha(alpha)-alkylation reaction of ketones with alcohols. The activities of iridium complexes (Ir1-5) were much more efficient than ruthenium complexes (Ru1-5). The highest activity for both reactions was observed for the complex (Ir2 ) with pyridine-2-carboxylate. The Ir hydride species was monitored for both reactions. (C) 2020 Elsevier B.V. All rights reserved.

Welcome to talk about 98-97-5, If you have any questions, you can contact Pakyapan, B; Kavukcu, SB; Sahin, ZS; Turkmen, H or send Email.. Quality Control of Pyrazine-2-carboxylic acid

Reference:
Patent; Chevron Research Company; US4732894; (1988); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Dumpala, RMR; Srivastava, A; Rawat, N in [Dumpala, Rama Mohana Rao; Srivastava, Ashutosh; Rawat, Neetika] Bhabha Atom Res Ctr, Radiochem Div, Mumbai 400085, Maharashtra, India published Experimental and theoretical approach to probe the aquatic speciation of transuranic (neptunyl) ion in presence of two omnipresent organic moieties in 2021, Cited 53. Name: Pyrazine-2-carboxylic acid. The Name is Pyrazine-2-carboxylic acid. Through research, I have a further understanding and discovery of 98-97-5.

Pyrazines are omnipresent in nature and have their occurrence in plants, microbes, food supplies, marine arenas. The present studies aimed at aquatic speciation of the neptunyl ion (NpO2+) with two pyrazine compounds namely pyrazine monocarboxylic acid (PMC) and pyrazine dicarboxylic acid (PDC). Absorption spectrophotometry was used to probe the stability, speciation and spectral properties for the complexation process. NpOO2+ forms a more stable complex with PMC than PDC for 1:1 (ML), while for 1:2 (ML2) the opposite trend is observed. The extent of shift in lambda(max), which is also an indicator for the strength of complexation, reflected similar trends for the complexation process. Isothermal titration calorimetry was employed to determine the enthalpies of complex formation, which is found to be endothermic. The complexation process is entropy driven. Linear free energy correlations were established to retrieve the coordination modes of the complexes. The variation in peak potentials (the cyclic voltammograms) with change in pH and metal to ligand ratio were explored to understand redox speciation, electron transfer kinetics and Eh-pH characteristics for the interaction of NpOO2+ with pyrazine carboxylate ligands. Density functional theory calculations were employed to optimize the geometries and to calculate the bond distances and partial charges on key atoms of the optimized geometries. The theoretical calculations helped to reveal the contributions from two different configurations of the same geometry towards the optical absorption. The bond distances and partial charges estimated theoretically helped to understand the aqueous interactions at the molecular level. (C) 2021 Elsevier Ltd. All rights reserved.

Name: Pyrazine-2-carboxylic acid. Bye, fridends, I hope you can learn more about C5H4N2O2, If you have any questions, you can browse other blog as well. See you lster.

Reference:
Patent; Chevron Research Company; US4732894; (1988); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

An article Role of pi-conjugation on the coordination behaviour, substitution kinetics, DNA/BSA interactions, and in vitro cytotoxicity of carboxamide palladium(II) complexes WOS:000653084400001 published article about COLON-CANCER CELLS; PLATINUM(II) COMPLEXES; MOLECULAR DOCKING; PT(II) COMPLEXES; BENIGN SYNTHESIS; DNA CLEAVAGE; CT-DNA; LIGANDS; BINDING; ANTICANCER in [Omondi, Reinner O.; Ojwach, Stephen O.] Univ KwaZulu Natal, Sch Chem & Phys, Private Bag X01, ZA-3209 Pietermaritzburg, South Africa; [Sibuyi, Nicole R. S.; Fadaka, Adewale O.; Meyer, Mervin] Univ Western Cape, Dept Biotechnol, Bag X17, ZA-7535 Cape Town, South Africa; [Jaganyi, Deogratius] Mt Kenya Univ, Sch Pure & Appl Sci, POB 342-01000, Thika, Kenya; [Jaganyi, Deogratius] Durban Univ Technol, Fac Sci Appl, Dept Chem, POB 1334, ZA-4000 Durban, South Africa in 2021, Cited 70. The Name is Pyrazine-2-carboxylic acid. Through research, I have a further understanding and discovery of 98-97-5. Application In Synthesis of Pyrazine-2-carboxylic acid

Treatments of N-(pyridin-2-ylmethyl)pyrazine-2-carboxamide (L-1), N-(quinolin-8-yl)pyrazine-2-carboxamide (L-2), N-(quinolin-8-yl)picolinamide (L-3) and N-(quinolin-8-yl)quinoline-2-carboxamide (L-4) with [PdCl2(NCMe)](2) afforded the corresponding Pd(ii) complexes, [Pd(L-1)Cl] (PdL1); [Pd(L-2)Cl] (PdL2); [Pd(L-3)Cl] (PdL3); and [Pd(L-4)Cl] (PdL4) in moderate yields. Structural characterisation of the compounds was achieved by NMR and FT-IR spectroscopies, elemental analyses and single crystal X-ray crystallography. The solid-state structures of complexes PdL2-PdL4 established the presence of one tridentate carboxamide and Cl ligands around the Pd(ii) coordination sphere, to give distorted square planar complexes. Electrochemical investigations of PdL1-PdL4 showed irreversible one-electron oxidation reactions. Kinetics reactivity of the complexes towards bio-molecules, thiourea (Tu), l-methionine (L-Met) and guanosine 5 ‘-diphosphate disodium salt (5 ‘-GMP) decreased in the order: PdL1 > PdL2 > PdL3 > PdL4, in tandem with the density functional theory (DFT) data. The complexes bind favourably to calf thymus (CT-DNA), and bovine serum albumin (BSA), and the order of their interactions agrees with the substitution kinetics trends. The in vitro cytotoxic activities of PdL1-PdL4 were examined in cancer cell lines A549, PC-3, HT-29, Caco-2, and HeLa, and a normal cell line, KMST-6. Overall, PdL1 and PdL3 displayed potent cytotoxic effects on A549, PC-3 HT-29 and Caco-2 comparable to cisplatin. All the investigated complexes exhibited lower toxicity on normal cells than cisplatin.

Application In Synthesis of Pyrazine-2-carboxylic acid. Bye, fridends, I hope you can learn more about C5H4N2O2, If you have any questions, you can browse other blog as well. See you lster.

Reference:
Patent; Chevron Research Company; US4732894; (1988); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Authors Samie, A; Salimi, A; Garrison, JC in ROYAL SOC CHEMISTRY published article about INDEPENDENT CHEMICAL-SHIFTS; THROUGH-SPACE INTERACTIONS; FACE-TO-FACE; HYDROGEN-BOND; CRYSTAL-STRUCTURE; CURRENT-DENSITY; SANDWICH; SUBSTITUENTS; COMPLEXES; ENERGIES in [Samie, Ali; Salimi, Alireza] Ferdowsi Univ Mashhad, Fac Sci, Dept Chem, Mashhad, Iran; [Garrison, Jered C.] Univ Nebraska Med Ctr, Dept Pharmaceut Sci, Omaha, NE USA in 2019, Cited 72. COA of Formula: C5H4N2O2. The Name is Pyrazine-2-carboxylic acid. Through research, I have a further understanding and discovery of 98-97-5

Based on the crystal engineering concept, four new esters containing alpha and beta-substituted naphthalene rings were designed, synthesized and fully characterized. The crystal structure analysis of the designed molecules revealed that the C-H-based interactions especially C-HMIDLINE HORIZONTAL ELLIPSIS pi have a significant role in the stabilization of crystal architectures. Regarding the molecular structure of naphthalene rings, one can find that bond lengths are divided into two groups (shorter and longer) so that relative localization is likely to occur in this system. Since pi-electron localization in aromatic rings has been previously introduced as responsible for stronger pi-stacking, this issue was investigated through C-HMIDLINE HORIZONTAL ELLIPSIS pi interaction in this study. Cambridge Structural Database (CSD) analysis was performed by exploration of suitable geometries for C-HMIDLINE HORIZONTAL ELLIPSIS pi(c) and C-HMIDLINE HORIZONTAL ELLIPSIS pi(e) in naphthalene and phenol systems (pi(c) and pi(e) are the centre and edge of the aromatic rings, respectively). The tendency factor (TF) of the C-H moiety toward ring bonds as a new CSD-based criterion was used to detect some of the resonance forms in aromatic rings. The results indicated that C-HMIDLINE HORIZONTAL ELLIPSIS pi(e) is a ubiquitous interaction which can be employed as an experimental probe for the detection of pi-localization in naphthalene rings. Systematic experimental studies, structural evidence and computational results on the title compounds confirmed the relative pi-electron localization, as well.

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Reference:
Patent; Chevron Research Company; US4732894; (1988); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Walczak, M; Chryplewicz, A; Olewinska, S; Psurski, M; Winiarski, L; Torzyk, K; Oleksyszyn, J; Sienczyk, M in [Walczak, Maciej; Chryplewicz, Agnieszka; Olewinska, Sandra; Winiarski, Lukasz; Torzyk, Karolina; Oleksyszyn, Jozef; Sienczyk, Marcin] Wroclaw Univ Sci & Technol, Dept Organ & Med Chem, Fac Chem, Wybrzeze Wyspianskiego 27, PL-50370 Wroclaw, Poland; [Psurski, Mateusz] Polish Acad Sci, Hirszfeld Inst Immunol & Expt Therapy, Dept Expt Oncol, Weigla 12, PL-53114 Wroclaw, Poland published Phosphonic Analogs of Alanine as Acylpeptide Hydrolase Inhibitors in 2021, Cited 54. Quality Control of Pyrazine-2-carboxylic acid. The Name is Pyrazine-2-carboxylic acid. Through research, I have a further understanding and discovery of 98-97-5.

Acylpeptide hydrolase is a serine protease, which, together with prolyl oligopeptidase, dipeptidyl peptidase IV and oligopeptidase B, belongs to the prolyl oligopeptidase family. Its primary function is associated with the removal of N-acetylated amino acid residues from proteins and peptides. Although the N-acylation occurs in 50-90 % of eukaryotic proteins, the precise functions of this modification remains unclear. Recent findings have indicated that acylpeptide hydrolase participates in various events including oxidized proteins degradation, amyloid beta-peptide cleavage, and response to DNA damage. Considering the protein degradation cycle cross-talk between acylpeptide hydrolase and proteasome, inhibition of the first enzyme resulted in down-regulation of the ubiquitin-proteasome system and induction of cancer cell apoptosis. Acylpeptide hydrolase has been proposed as an interesting target for the development of new potential anticancer agents. Here, we present the synthesis of simple derivatives of (1-aminoethyl)phosphonic acid diaryl esters, phosphonic analogs of alanine diversified at the N-terminus and ester rings, as inhibitors of acylpeptide hydrolase and discuss the ability of the title compounds to induce apoptosis of U937 and MV-4-11 tumor cell lines.

Welcome to talk about 98-97-5, If you have any questions, you can contact Walczak, M; Chryplewicz, A; Olewinska, S; Psurski, M; Winiarski, L; Torzyk, K; Oleksyszyn, J; Sienczyk, M or send Email.. Quality Control of Pyrazine-2-carboxylic acid

Reference:
Patent; Chevron Research Company; US4732894; (1988); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

An article LMP2 Inhibitors as a Potential Treatment for Alzheimer’s Disease WOS:000526405300024 published article about ANTIINFLAMMATORY DRUGS; IMMUNOPROTEASOME; DESIGN; CELLS; RISK in [Bhattarai, Deepak; Lee, Min Jae; Miller, Zachary; Kim, Kyung Bo] Univ Kentucky, Dept Pharmaceut Sci, Lexington, KY 40536 USA; [Baek, Ahruem; Baek, Yu Mi; Kim, Dong-Eun] Konkuk Univ, Dept Biosci & Biotechnol, Seoul 05029, South Korea; [Yeo, In Jun; Hong, Jin Tae] Chungbuk Natl Univ, Coll Pharm, Cheongju 28160, Chungbuk, South Korea; [Lee, Sukyeong] Baylor Coll Med, Verna & Marrs McLean Dept Biochem & Mol Biol, Houston, TX 77030 USA in 2020, Cited 43. Category: Pyrazines. The Name is Pyrazine-2-carboxylic acid. Through research, I have a further understanding and discovery of 98-97-5

The immunoproteasome (iP), an inducible proteasome variant harboring three immunosubunits, low molecular mass polypeptide-2 (LMP2), multicatalytic endopeptidase complex subunit-1, and low molecular mass polypeptide-7 (LMP7), is involved in multiple facets of inflammatory responses. We recently reported that YU102, a dual inhibitor of the iP subunit LMP2 and the constitutive proteasome catalytic subunit beta 1, ameliorates cognitive impairments in mouse models of Alzheimer’s disease (AD) independently of amyloid deposits. To investigate whether inhibition of LMP2 is sufficient to improve the cognitive functions of AD mice, here we prepared 37 YU102 analogues and identified a potent LMP2 inhibitor DB-310 (28) (IC50: 80.6 nM) with improved selectivity and permeability in cells overexpressing ABCB1 transporters. We show that DB-310 induces suppression of IL-1 alpha production in microglia cells and improves cognitive functions in the Tg2576 transgenic mouse model of AD. This study supports that inhibition of LMP2 is a promising therapeutic strategy for treatment of AD.

Bye, fridends, I hope you can learn more about C5H4N2O2, If you have any questions, you can browse other blog as well. See you lster.. Category: Pyrazines

Reference:
Patent; Chevron Research Company; US4732894; (1988); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem