Month: January 2022

In 2019 J CHEM INF MODEL published article about MOLECULAR-DYNAMICS; SHAPE COMPLEMENTARITY; BINDING; DOCKING; SYSTEM; IDENTIFICATION; TRANSLATION; CONSTRAINTS; MUTATION; INSIGHT in [Rehman, Ashfaq Ur; Liu, Hao; Chen, Hai-Feng] Shanghai Jiao Tong Univ, Sch Life Sci & Biotechnol, Natl Expt Teaching Ctr Life Sci & Biotechnol, State Key Lab Microbial Metab,Dept Bioinformat &, Shanghai 200240, Peoples R China; [Chen, Hai-Feng] Shanghai Ctr Bioinformat Technol, Shanghai 200235, Peoples R China; [Khan, Muhammad Tahir; Malik, Shaukat Iqbal] Capital Univ Sci & Technol, Dept Bioinformat & Biosci, Islamabad 44000, Pakistan; [Rehman, Ashfaq Ur; Wadood, Abdul] Abdul Wali Khan Univ Marden, Dept Biotechnol, Mardan 23200, Pakistan in 2019, Cited 62. The Name is Pyrazine-2-carboxylic acid. Through research, I have a further understanding and discovery of 98-97-5. Formula: C5H4N2O2

Pyrazinamide (PZA) is an essential first line antitubercular drug, which plays a crucial role in tuberculosis treatment. The PZA, which is considered as a pro-drug needs an enzyme of mycobacterial pyrazinamidase (PZase) for its conversion into an active form pyrazinoic acid. Further, this active form of PZA inhibits the ribosomal proteins Si, which facilitates the transfer-mRNA complex formation throughout the translation. The spontaneous mutations in RpsA have been found to be associated with PZA drug resistance. However, the drug resistance mechanism is still unclear. Furthermore, there is no such information available about the structural dynamics of RpsA protein because of mutations that confer Pyrazinoic acid resistance. Moreover, a total of 18 clinical PZA-resistant isolates were investigated and found to be pncA(WT), which allowed exploration of the resistance mechanism of RpsA in the mutated state. Samples were repeated for the drug susceptibility testing followed by RpsA gene sequencing. A total of 11 clinical isolates harbored a total of 15 mutations. Almost half of the total strains (7/15) were observed to be in the conserved region of RpsA and known as Mycobacterium tuberculosis C-terminal domain. In the current study, (2/7) mutation T370P (mutant 1) and W403G (mutant 2) were explored to ensure the RpsA resistance mechanism through essential dynamics simulation. The essential dynamics study results revealed that the distal loop mutations drastically altered the conformation of RpsA both in the absence () and presence (+) of pyrazinoic acid drug for two reasons: (1) dramatic alteration or reduction in the binding pattern of pyrazinoic acid with active site residues observed and (2) a clear image of the opening and closing switching mechanism was seen upon the distal site mutation on nearby 3(10)-helixes beside the pyrazinoic acid binding site. This switch was found to consistently remain closed only in wild type systems, while it was open in the mutant systems. We called such distance impact an allosteric effect. The overall mechanistic investigations will provide useful information behind drug resistance for better understanding to manage tuberculosis.

Welcome to talk about 98-97-5, If you have any questions, you can contact Rehman, AU; Khan, MT; Liu, H; Wadood, A; Malik, SI; Chen, HF or send Email.. Formula: C5H4N2O2

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

An article Discovery of Novel Peptidomimetic Boronate ClpP Inhibitors with Noncanonical Enzyme Mechanism as Potent Virulence Blockers in Vitro and in Vivo WOS:000526404600023 published article about AUREUS STRESS TOLERANCE; STAPHYLOCOCCUS-AUREUS; PROTEASE; INSIGHTS; CLEAVAGE; REVEAL; ROLES in [Ju, Yuan; He, Lihui; Zhou, Yuanzheng; Yang, Tao; Sun, Ke; Song, Rao; Yang, Yang; Li, Chengwei; Bao, Rui; Luo, Youfu] Sichuan Univ, State Key Lab Biotherapy, Collaborat Innovat Ctr Biotherapy, West China Hosp, Chengdu 610041, Peoples R China; [Ju, Yuan; He, Lihui; Zhou, Yuanzheng; Yang, Tao; Sun, Ke; Song, Rao; Yang, Yang; Li, Chengwei; Bao, Rui; Luo, Youfu] Sichuan Univ, Canc Ctr, Collaborat Innovat Ctr Biotherapy, West China Hosp, Chengdu 610041, Peoples R China; [Sang, Zitai] Luoyang Normal Univ, Inst Life Sci, Luoyang 471934, Henan, Peoples R China in 2020, Cited 53. The Name is Pyrazine-2-carboxylic acid. Through research, I have a further understanding and discovery of 98-97-5. Safety of Pyrazine-2-carboxylic acid

Caseinolytic protease P (ClpP) is considered as a promising target for the treatment of Staphylococcus aureus infections. In an unbiased screen of 2632 molecules, a peptidomimetic boronate, MLN9708, was found to be a potent suppressor of SaClpP function. A time-saving and cost-efficient strategy integrating in silico position scanning, multistep miniaturized synthesis, and bioactivity testing was deployed for optimization of this hit compound and led to fast exploration of structure-activity relationships. Five of 150 compounds from the miniaturized synthesis exhibited improved inhibitory activity. Compound 43Hf was the most active inhibitor and showed reversible covalent binding to SaClpP while did not destabilize the tetradecameric structure of SaClpP. The crystal structure of 43Hf-SaClpP complex provided mechanistic insight into the covalent binding mode of peptidomimetic boronate and SaClpP. Furthermore, 43Hf could bind endogenous ClpP in S. aureus cells and exhibited significant efficacy in attenuating S. aureus virulence in vitro and in vivo.

Safety 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

Recently I am researching about AQUEOUS-SOLUTION; EQUILIBRIUM-CONSTANTS; CARBOXYLIC-ACIDS; URANIUM(VI); CRYSTAL; ION; CHEMISTRY; LIGAND, Saw an article supported by the National Science Foundation of ChinaNational Natural Science Foundation of China (NSFC) [11675156, 91326110, 21790372, 21822606]. Published in ROYAL SOC CHEMISTRY in CAMBRIDGE ,Authors: Lv, LN; Chen, BH; Liu, J; Chen, J; Xu, C; Yang, YQ. The CAS is 98-97-5. Through research, I have a further understanding and discovery of Pyrazine-2-carboxylic acid. Product Details of 98-97-5

Complexation of U(vi) with pyridazine-3-carboxylate (PDZ) and pyrazine-2-carboxylate (PAZ) was studied by spectrophotometry, potentiometry and microcalorimetry in 1.0 mol dm(-3) NaClO4. Three complexes, [UO2L](+), UO2L2(aq) and [UO2L3](-), were identified and their stability constants (log) and the corresponding formation enthalpies were determined. The thermodynamic parameters indicate that the formation of the three complexes is endothermic and driven exclusively by entropy. H-1 and C-13-NMR data provide insight into the coordination modes of the complexes which corroborate with the thermodynamic data. Ligands chelate to U(vi) via (2)(N,O) coordination mode in complexes [UO2L](+) and UO2L2(aq). The crystal structures of four U(vi) complexes, [(UO2)(PAZ)(2)(H2O)]H2O(i), [(UO2)(PDZ)(2)(H2O)](ii), [(UO2)(PDZ)(3)Na2ClO4]2H(2)O(iii), and [(UO2)(2)(PDZ)(4)(H2O)(2)]2H(2)O(iv), were determined by single-crystal X-ray diffraction and compared with the U(vi) complex with picolinate (PA) (CH6N3)[UO2(PA)(3)] in the literature. The structure data suggest that the carboxylates coordinate with uranium in O?C-O-U mode. The strengths of the U-O-C-C-N chelate cycles in the U(vi)/L complexes decrease with the trend of PA > PDZ > PAZ, which is in great agreement with the trend of thermodynamic parameters in aqueous solutions. It is interesting that in compound II two PDZ molecules coordinate with U(vi) in cis-planar positions via (2)(N,O) mode, but in other metal complexes of the three ligands having the same (2)(N,O) coordination mode the two ligand molecules are all in trans-arrangement. In the dimeric complex IV, one ligand coordinate with U(vi) in (2)(N,O) mode, while the other does it in (2)-L-(2)(O:O) mode respectively.

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

Recommanded Product: 98-97-5. In 2021 BIOORG CHEM published article about LEISHMANIA; INFECTION; DOCKING in [Khatoon, Saira; Hameed, Shahid; Naseer, Muhammad Moazzam] Quaid I Azam Univ, Dept Chem, Islamabad 45320, Pakistan; [Aroosh, Aiman; Islam, Arshad; Kalsoom, Saima; Yasinzai, Masoom] Int Islamic Univ, Fac Basic & Appl Sci, Suleiman Bin Abdullah Aba Akhail Ctr Interdiscipl, Islamabad 44000, Pakistan; [Islam, Arshad] Govt Lady Reading Hosp Med Teaching Inst, Dept Pathol, Peshawar, KPK, Pakistan; [Ahmad, Faisal] Quaid I Azam Univ, Natl Ctr Bioinformat, Islamabad 45320, Pakistan; [Abbasi, Sumra Wajid] Natl Univ Med Sci, Dept Biol Sci, Rawalpindi, Pakistan in 2021, Cited 48. The Name is Pyrazine-2-carboxylic acid. Through research, I have a further understanding and discovery of 98-97-5.

Leishmaniasis being one of the six major tropical diseases that affects nearly 0.7-1.3 million people annually, has so far limited and high toxic therapeutic options. Herein, we report the synthesis, in silico, and in vitro evaluations of novel coumarin-incorporated isatin hydrazones (Spf-1 – Spf-10) as highly potent and safe antileishmanial agents. Molecular docking was initially carried out to decipher the binding confirmation of lead molecules towards the active cavity of the target protein (Leishmanolysin gp63) of Leishmania tropica. Among all the docked compounds, only Spf-6, Spf-8, and Spf-10 showed high binding affinities due to a pattern of strong conventional hydrogen bonds and hydrophobic pi-interactions. The molecular dynamics simulations showed the stable pattern of such bonding and structure-based confirmation with a time scale of 50 ns towards the top compound (Spf-10) and protein. These analyses affirmed the high stability of the system. Three out of ten compounds evaluated for their antileishmanial activity against Leishmania tropica promastigotes and amastigotes were found to be active at micromolar concentrations (IC50 range 0.1-4.13 mu mol/L), and most importantly, they were also found to be highly biocompatible when screened for their toxicity in human erythrocytes.

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

Recommanded Product: Pyrazine-2-carboxylic acid. Authors Drozd, KV; Manin, AN; Voronin, AP; Perlovich, GL in ACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD published article about in [Drozd, K., V; Manin, A. N.; Voronin, A. P.; Perlovich, G. L.] RAS, GA Krestov Inst Solut Chem, Ivanovo 153045, Russia in 2021, Cited 70. The Name is Pyrazine-2-carboxylic acid. Through research, I have a further understanding and discovery of 98-97-5

The thermophysical characteristics and decomposition of pyrazinoic (POA), dipicolinic (DPA), and quinolinic (QNA) acids have been studied by differential scanning calorimetry (DSC), thermogravimetric analysis (TG) and mass-spectrometry. The transpiration method has been used to measure the vapour pressures as a function of the POA, DPA or QNA temperature. It has been found that QNA remains thermally stable in the solid form up to the temperature of 367.15 K, and further heating causes its decarboxylation and irreversible conversion to nicotinic acid. The standard molar enthalpies, entropies, and Gibbs energies of sublimation for POA, DPA and QNA have been calculated. A comparative study of five calculation schemes for sublimation enthalpy estimation (periodic Density Functional Theory computations (DFT-D3), Quantum Theory of Atoms in Molecules (QTAIM), Gavezzotti’s Coulomb-London-Pauli model (CLP and PIXEL) and CrystalExplorer CE-B3LYP) has been conducted. The sublimation thermodynamic functions of the compounds studied by the correlation method have been estimated. When applied to the objects of this study, the method proved to be a quick, convenient and inexpensive way to evaluate the sublimation thermodynamic functions of molecular crystals using only the melting temperature of the compound. (C) 2020 Elsevier Ltd.

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

Quality Control of Pyrazine-2-carboxylic acid. Reddyrajula, R; Dalimba, U in [Reddyrajula, Rajkumar; Dalimba, Udayakumar] Natl Inst Technol Karnataka, Dept Chem, Organ Chem Lab, Mangalore 575025, India published The bioisosteric modification of pyrazinamide derivatives led to potent antitubercular agents: Synthesis via click approach and molecular docking of pyrazine-1,2,3-triazoles in 2020, Cited 38. The Name is Pyrazine-2-carboxylic acid. Through research, I have a further understanding and discovery of 98-97-5.

Tuberculosis remains as a major public health risk which causes the highest mortality rate globally and an improved regimen is required to treat the drug-resistant strains. Pyrazinamide is a first-line antitubercular drug used in combination therapy with other anti-TB drugs. Herein, we describe the modification of pyrazinamide structure using bioisosterism and rational approaches by incorporating the 1,2,3-triazole moiety. Three sets of pyrazine-1,2,3-triazoles (3a-o, 5a-o and 9a-l) are designed, synthesized and evaluated for their in vitro inhibitory potency against mycobacterium tuberculosis H(37)Rv. The pyrazine-1,2,3-triazoles synthesized through the bioisosteric modification displayed improved activity as compared to rationally modified pyrazine-1,2,3-triazoles. Among 42 title compounds, seven derivatives demonstrated significant anti-tubercular activity with the MIC of 1.56 mu g/mL, which are two-fold more potent than the parent compound pyrazinamide. Further, the synthesized pyrazinamide analogs demonstrated moderate inhibition activity against several bacterial strains and possessed an acceptable in vitro cytotoxicity profile as well. Additionally, the activity profile of pyrazine-1,2,3-triazoles was validated by performing the molecular docking studies against the Inh A enzyme. Furthermore, in silico ADME prediction revealed good oral bioavailability for the potent molecules.

Welcome to talk about 98-97-5, If you have any questions, you can contact Reddyrajula, R; Dalimba, U or send Email.. Quality Control of Pyrazine-2-carboxylic acid

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

I found the field of Engineering; Materials Science; Mechanics very interesting. Saw the article Inhibition efficiency of pyrazinecarboxylic acid on mild steel in acidic environment published in 2021. Quality Control of Pyrazine-2-carboxylic acid, Reprint Addresses Kelesoglu, A (corresponding author), Cukurova Univ, Fac Sci & Letters, Chem Dept, Adana, Turkey.. The CAS is 98-97-5. Through research, I have a further understanding and discovery of Pyrazine-2-carboxylic acid

Pyrazinecarboxylic acid (PCA) was examined as a potential corrosion inhibitor for mild steel (MS) in 0.5 M HCl environment. The methods of electrochemical impedance spectroscopy (EIS), linear polarization resistance (LPR), as well potentiodynamic (PD) polarization were utilized. Furthermore, atomic force microscopy (AFM) and quantum chemical calculations were utilized. PD polarization curves demonstrated that PCA exhibited mixed inhibitor behavior. Scanning electron microscopy (SEM) offered the creation of an adsorptive layer on the surface of MS which prevented the steel against corrosive specimens. Furthermore, density functional theory (DFT) presented good agreement with electrochemical experimental results. The adsorption equilibrium constant (k(ads)) value was calculated to be 3.704 x 10(4) M-1 which was related to a high proportion of inhibitor on the surface. In the presence of 1.0 mM PCA, inhibition efficiency was determined as 95.2% from EIS results.

Quality Control 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

SDS of cas: 98-97-5. In 2019 EUR J DRUG METAB PH published article about RENAL-FUNCTION; METABOLITES; CLEARANCE; RIFAMPIN in [Mugabo, Pierre; Mulubwa, Mwila] Univ Western Cape, Sch Pharm, Private Bag X17, ZA-7535 Bellville, Cape Town, South Africa in 2019, Cited 28. The Name is Pyrazine-2-carboxylic acid. Through research, I have a further understanding and discovery of 98-97-5.

Background and ObjectivesPyrazinamide, a drug used in the regimen for the treatment of drug-sensitive tuberculosis, is also used for the treatment of multidrug-resistant tuberculosis (MDR-TB). We aimed to describe the population pharmacokinetics of pyrazinamide and its major metabolite, pyrazinoic acid, in patients with MDR-TB and characterise the effects of demographic variables.MethodsThis was a non-randomised clinical study involving 51 adult patients admitted for the intensive phase of MDR-TB treatment. Blood samples were collected at pre-dose and at 0.5, 1, 1.5, 2, 3, 4, 8, 16 and 24h after drug administration. Plasma concentrations of pyrazinamide and pyrazinoic acid were analysed using a validated LC-MS/MS method. Nonlinear mixed-effects modelling using Monolix 2018R1 software was employed to estimate population pharmacokinetic parameters.ResultsA one-compartment pharmacokinetic model with transit compartment absorption process and first-order elimination best described the pyrazinamide and pyrazinoic acid concentration-time data. The estimated population pharmacokinetic parameters were 0.7h, 3.38h(-1), 57.1l, 4.37L/h and 10.5L/h for mean transit time, absorption rate constant, apparent distribution volume for pyrazinamide, and apparent clearance for pyrazinamide and pyrazinoic acid (CLm/F), respectively. These parameters were not affected by patient age, HIV status or sex. The parameter variability in CLm/F was the highest (83.5%), while the rest of the parameters ranged from 16.2 to 58%.ConclusionsThe developed population pharmacokinetic model adequately described the disposition of pyrazinamide and pyrazinoic acid and can be useful for dose determination of pyrazinamide in patients with MDR-TB.

SDS of cas: 98-97-5. Welcome to talk about 98-97-5, If you have any questions, you can contact Mugabo, P; Mulubwa, M or send Email.

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

An article Synthesis of pyripyropene derivatives and their pest-control efficacy WOS:000512216500017 published article about ACYL-COA; ASPERGILLUS-FUMIGATUS; CHEMICAL-MODIFICATION; STRUCTURE ELUCIDATION; INHIBITORS; POTENT; RESISTANCE; METABOLITE in [Guro, Kimihiko; Horikoshi, Ryo; Nakamura, Satoshi; Mitomi, Masaaki; Oyama, Kazuhiko] Meiji Seika Pharma Co Ltd, Agr & Vet Div, Agr & Vet Res Labs, Kohoku Ku, 760 Morooka Cho, Yokohama, Kanagawa, Japan; [Hirose, Tomoyasu; Sunazuka, Toshiaki; Omura, Satoshi] Kitasato Univ, Kitasato Inst Life Sci, Grad Sch Infect Control Sci, Tokyo, Japan in 2019, Cited 22. The Name is Pyrazine-2-carboxylic acid. Through research, I have a further understanding and discovery of 98-97-5. HPLC of Formula: C5H4N2O2

Pyripyropene A (PP-A), a secondary metabolite produced by filamentous fungi, shows insecticidal activity against agricultural insect pests. Synthesized PP derivatives also show a narrow insecticidal spectrum but high insecticidal activities against such sucking pests. PP-A has a low eco-toxicological impact and satisfies a prerequisite for next-generation insecticides. We investigated the effects of conversion of the 3-pyridyl and a-pyrone rings to other rings, as well as the effects of esterification, dehydration, and oxidization at the C-13 position in natural PP analogues, on the insecticidal activity and spectrum. The conversions of the 3-pyridyl and alpha-pyrone rings markedly reduced the insecticidal activity with a minimal impact on the spectrum, indicative of an important role for these rings in insecticidal activity. Some derivatives with modified structures at the C-13 position showed a higher inhibitory effect on the motility of canine heartworms and mosquito vectors than did PP-A, suggesting their utility as filaria control drugs.

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.. HPLC of Formula: C5H4N2O2

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

Recommanded Product: 98-97-5. Dong, XW; Zhang, JK; Xu, L; Che, JX; Cheng, G; Hu, XB; Sheng, L; Gao, AH; Li, J; Liu, T; Hu, YZ; Zhou, YB in [Dong, Xiao-Wu; Zhang, Jian-Kang; Che, Jin-Xin; Liu, Tao; Hu, Yong-Zhou] Zhejiang Univ, ZJU ENS Joint Lab Med Chem, Zhejiang Prov Key Lab Anticanc Drug Res, Hangzhou Inst Innovat Med,Coll Pharmaceut Sci, Hangzhou 310058, Zhejiang, Peoples R China; [Xu, Lei; Hu, Xiao-Bei; Sheng, Li; Gao, An-Hui; Li, Jia; Liu, Tao; Zhou, Yu-Bo] Chinese Acad Sci, Shanghai Inst Mat Med, State Key Lab Drug Res, Natl Ctr Drug Screening, Shanghai 201203, Peoples R China; [Xu, Lei; Hu, Xiao-Bei; Sheng, Li; Gao, An-Hui; Li, Jia; Zhou, Yu-Bo] Univ Chinese Acad Sci, 19A Yuquan Rd, Beijing 100049, Peoples R China; [Zhang, Jian-Kang] Zhejiang Univ City Coll, Sch Med, Hangzhou 310015, Zhejiang, Peoples R China; [Cheng, Gang] Zhejiang Chinese Med Univ, Coll Pharmaceut Sci, Hangzhou 311402, Zhejiang, Peoples R China published Covalent docking modelling-based discovery of tripeptidyl epoxyketone proteasome inhibitors composed of aliphatic-heterocycles in 2019, Cited 33. The Name is Pyrazine-2-carboxylic acid. Through research, I have a further understanding and discovery of 98-97-5.

The potential of specific proteasome inhibitors to act as anti-cancer agents has attracted intensive investigations. The proteasome can be covalently inhibited by epoxyketone derivatives via a two-step reaction. Several computational approaches have been developed to mimic the covalent binding event. Compound 1 composed of a six-membered heterocyclic ring was designed by using covalent docking. With a possible different binding mode from the clinical compound Carfilzomib, it occupied the 55 pocket of 20S proteasome and showed favorable inhibitory activity. Subsequently optimization and evaluation were taken place. Among these compounds, 11h demonstrated extraordinary in vitro inhibitory activity and selectivity, and good in vivo proteasome inhibitory activity, a favorable pharmacokinetic profile and xenograft tumor inhibition. The possible binding pattern of compound 11h against proteasome was further fully explored via calculations, providing a theoretical basis for finding potent proteasome inhibitors. (C) 2018 Elsevier Masson SAS. All rights reserved.

Recommanded Product: 98-97-5. Welcome to talk about 98-97-5, If you have any questions, you can contact Dong, XW; Zhang, JK; Xu, L; Che, JX; Cheng, G; Hu, XB; Sheng, L; Gao, AH; Li, J; Liu, T; Hu, YZ; Zhou, YB or send Email.

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