Brief introduction of 1458-01-1

In the field of chemistry, the synthetic routes of compounds are constantly being developed and updated. I will also mention this compound in other articles, Methyl 3,5-diamino-6-chloropyrazine-2-carboxylate, other downstream synthetic routes, hurry up and to see.

Synthetic Route of 1458-01-1, The chemical industry reduces the impact on the environment during synthesis 1458-01-1, name is Methyl 3,5-diamino-6-chloropyrazine-2-carboxylate, I believe this compound will play a more active role in future production and life.

Preparation 1 3-Chloro-pyrazine-2,6-diamine Lithium hydroxide (12.4 g, 0.30 mol) was added to a stirred suspension of 3,5-diamino-6-chloro-pyrazine-2-carboxylic acid methyl ester (20 g, 99 mmol) in methanol (300 ml) and water (120 ml) and the reaction heated at 90¡ã C. for 1.5 hours before allowing to cool to room temperature. The reaction was concentrated in vacuo to afford a yellow slurry and this was suspended in 1,4-dioxane (350 ml) and 2M aqueous HCl solution (200 ml,) was added. The mixture was heated at 100¡ã C. for 2 hours and then allowed to cool before removing the 1,4-dioxane in vacuo. The resulting aqueous solution was taken to pH 8 using sodium carbonate (saturated aqueous) and extracted into ethyl acetate (3*300 ml). The combined organic layers were washed with brine (300 ml), dried (Na2SO4) and concentrated in vacuo to afford a yellow solid (11.7 g, 82percent). 1H-NMR (d6-DMSO): 5.95 (br s, 2H), 6.02 (br s, 2H), 6.82 (s, 1H). MS m/z 147 [MH]+

In the field of chemistry, the synthetic routes of compounds are constantly being developed and updated. I will also mention this compound in other articles, Methyl 3,5-diamino-6-chloropyrazine-2-carboxylate, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; Pfizer Limited; US2007/105872; (2007); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

The important role of 5521-58-4

In the field of chemistry, the synthetic routes of compounds are constantly being developed and updated. I will also mention this compound in other articles, 5-Methylpyrazin-2-amine, other downstream synthetic routes, hurry up and to see.

Adding a certain compound to certain chemical reactions, such as: 5521-58-4, name is 5-Methylpyrazin-2-amine, belongs to Pyrazines compound, can increase the reaction rate and produce products with better performance than those obtained under traditional synthetic methods. Here is a downstream synthesis route of the compound 5521-58-4, Quality Control of 5-Methylpyrazin-2-amine

3-{[5-(Azetidin-1-ylcarbonyl)pyrazin-2-yl]oxy}-5-[(1S)-2-methoxy-1-methylethoxy]-benzoic acid (1.0 eq), (1.00 mol eq), 5-methylpyrazin-2-amine (1.12 mol eq) and 2-methyltetrahydrofuran (2.00 rel vols) were charged to a vessel and stirred at 20 C. N-methylmorpholine (5.00 mol eq) was added followed by a line-wash with 2-methyl-tetrahydrofuran (0.50 rel vols). A 50 wt % solution of 1-propanephosphonic acid cyclic anhydride (T3P) in 2-methyltetrahydrofuran (1.70 mol eq) was charged followed by a line wash with 2-methyltetrahydrofuran (0.50 rel vols). The resulting mixture was heated to 78 C. over 30 minutes and the clear yellow solution was held at 78 C. for roughly 22 hours, then checked for acceptable conversion. At the end of reaction the solution was further diluted with 2-methyltetrahydrofuran (7.00 rel vols) and the temperature was adjusted to 45 C. 5 wt % aq. sodium bicarbonate solution (6.00 rel vols) was slowly added over 30 mins to the stirring solution causing gas evolution. After 15 minutes stirring was turned off and the phases were allowed to separate over 30 minutes. The lower aqueous phase was drained off 20 wt % aq. phosphoric acid (3.30 rel vols) was charged to the stirring organic phase. After 15 minutes stirring the phases were allowed to separate and the lower aqueous phase was drained off again. A mixture of 20 wt % aq. phosphoric acid (1.50 rel vols) and water (1.50 rel vols) was charged to the stirring organic phase. After 15 minutes, stirring was turned off and the mixture held overnight for phase separation. The lower (aqueous) phase was drained off again. 5 Wt % aq. sodium bicarbonate (4.50 rel vols) was added over at least 10 mins to the stirring solution. After phase separation the lower (aqueous) phase was run off again. The resulting solution was dried by azeotropic distillation to a concentration of approximately 241 mg/g, collecting around 0.48 rel vols of the lower distillate phase. Heptane (1.60 rel vols) was added over 10 mins to the dry solution at above 50 C. before the batch was cooled to 40 C. The solution was seeded with 3-{[5-(azetidin-1-ylcarbonyl)pyrazin-2-yl]oxy}-5-[(1S)-2-methoxy-1-methylethoxy]-N-(5-methylpyrazin-2-yl)benzamide (Form 1 Seed, 0.0010 rel wt) before an overnight temperature program was applied: held at 40 C. for 2 hrs; cooled to 35 C. at 0.1 C./min (50 minutes); held for 2 hours; cooled to 30 C. at 0.1 C./min (50 minutes); held for 2 hours; cooled to 0 C. at 0.1 C./min (300 minutes); and held for at least 2 hours. After crystallisation overnight, further heptane (4.1 rel vols) was added over 2.0 hours to reduce losses to liquors to <4.0 mg/mL. The suspension was then filtered followed by a line rinse with a pre-mixed solution of heptane (2.10 rel vols) and 2-methyltetrahydrofuran (0.90 rel vols) and transferred to a filtration apparatus. The filter cake was dried to constant weight at 40 C. to furnish crude 3-{[5-(azetidin-1-ylcarbonyl)pyrazin-2-yl]oxy}-5-[(1S)-2-methoxy-1-methylethoxy]-N-(5-methylpyrazin-2-yl)benzamide in 86-89% as Form I. In the field of chemistry, the synthetic routes of compounds are constantly being developed and updated. I will also mention this compound in other articles, 5-Methylpyrazin-2-amine, other downstream synthetic routes, hurry up and to see. Reference:
Patent; AstraZeneca AB; US2010/210841; (2010); A1;,
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Brief introduction of 875781-43-4

According to the analysis of related databases, 875781-43-4, the application of this compound in the production field has become more and more popular.

In the chemical reaction process, reaction time, type of solvent, can easily affect the result of the reaction, thereby determining the yield and properties of the reaction product. An updated downstream synthesis route of 875781-43-4 as follows. COA of Formula: C6H4BrN3

Method AStep 1(2-Bromo-7-hydroxymethyl-pyrrolo [2,3 -b]pyrazin-5 -yl)-methanolTo a partial suspension of 2-bromo-5H-pyrrolo[2,3-b]pyrazine (5.0 g, 25.2 mmol) in 1 ,4-dioxane (100 mL) was added 2.0 M aqueous NaOH (25 mL, 50.0 mmol) and 37% aqueous formaldehyde (19 mL, 252 mmol). The dark homogenous reaction mixture was stirred at room temperature overnight. The organics were evaporated under reduced pressure. The aqueous layer was neutralized with 1.0 M HC1 and extracted with EtOAc (2x). The combined organics were concentrated to afford 2.6 g of an orange solid. Upon standing, a thick brown precipitate formed in the aqueous layer. The precipitate was collected by filtration and dried. The brown solid was extracted with hot 10% MeOH/EtOAc (3 x 200 mL). The extracts were combined and evaporated to provide an additional 3.05 g of orange solid. Overall yield was 5.65 g (87%) of (2- bromo-7-hydroxymethyl-pyrrolo[2,3-b]pyrazin-5-yl)-methanol. 1H NMR (DMSO-d6, 400 MHz): delta (ppm) 8.43 (s, 1H), 7.96 (s, 1H), 6.71 (t, J=7.3 Hz, 1H), 5.59 (d, J=7.6 Hz, 2H), 5.10 (t, J=5.3 Hz, 1H), 4.66 (d, J=5.6 Hz, 2H).

According to the analysis of related databases, 875781-43-4, the application of this compound in the production field has become more and more popular.

Reference:
Patent; F. HOFFMANN-LA ROCHE AG; CHEN, Shaoqing; DE VICENTE FIDALGO, Javier; HAMILTON, Matthew Michael; HERMANN, Johannes Cornelius; KENNEDY-SMITH, Joshua; LI, Hongju; LOVEY, Allen John; LUCAS, Matthew C.; LUK, Kin-Chun Thomas; LYNCH, Stephen M.; O’YANG, Counde; PADILLA, Fernando; SCHOENFELD, Ryan Craig; SIDDURI, Achyutharao; SOTH, Michael; WANG, Ce; WOVKULICH, Peter Michael; ZHANG, Xiaohu; WO2013/30138; (2013); A1;,
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Simple exploration of 77112-53-9

The basis of chemical reaction formula synthesis, the synthesis route is composed of some specific reactions and combined according to certain logical thinking. We look forward to the emergence of more reaction modes in the future.

Researchers who often do experiments know that organic synthesis is a process of preparing more complex target molecules from simple raw materials through one or more chemical reactions. Generally, it requires fewer steps, and cheap raw materials. 77112-53-9, name is Imidazo[1,2-a]pyrazine-2-carboxylic acid, A new synthetic method of this compound is introduced below., Safety of Imidazo[1,2-a]pyrazine-2-carboxylic acid

General procedure: Imidazo[1,2-a]pyrazine-2-carboxylic acid (5) (1.0 equiv.) Mukaiyama?s reagent and 2-chloro-1-methylpyridinium iodide (1.2 equiv.) were suspended in DMF (5.0 mL) under nitrogen atmosphere. Into the reaction mixture, aliphatic/aromatic amines (6a-l) (1.0 equiv.) and 1-methylimidazole (2.0 equiv.) were added. A homogeneous solution was formed after a gentle stirring. The reaction mixture was sealed in a microwave glass reactor and then irradiated by microwave oven at a constant temperature of 80 C with continuous stirring (1 min ramp, 15 min reaction time). After the reaction was completed, the solvent was removed through a rotary evaporator and the resulting residue was extracted by a biphasic system of 45 mL diethyl ether and 45 mL water. After the layer separation, the ether layer was dried by anhydrous sodium sulphate, followed by an evaporation of ether to get compounds 7a-l (Scheme-I).

The basis of chemical reaction formula synthesis, the synthesis route is composed of some specific reactions and combined according to certain logical thinking. We look forward to the emergence of more reaction modes in the future.

Reference:
Article; Jyothi, Boggavarapu; Madhavi, Nannapaneni; Asian Journal of Chemistry; vol. 32; 1; (2020); p. 84 – 90;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Introduction of a new synthetic route about 1209459-10-8

In the field of chemistry, the synthetic routes of compounds are constantly being developed and updated. I will also mention this compound in other articles, 2-Bromo-5-fluoropyrazine, other downstream synthetic routes, hurry up and to see.

Adding a certain compound to certain chemical reactions, such as: 1209459-10-8, name is 2-Bromo-5-fluoropyrazine, belongs to Pyrazines compound, can increase the reaction rate and produce products with better performance than those obtained under traditional synthetic methods. Here is a downstream synthesis route of the compound 1209459-10-8, COA of Formula: C4H2BrFN2

(R)-N-(6-(1-(1-((tert-butyldimethylsilyl)oxy)propan-2-yl)-1H-tetrazol-5-yl)pyridin-2-yl)-6-methoxy-1,2,3,4-tetrahydroisoquinoline-7-carboxamide (97 mg, 0.185 mmol), 2-bromo-5-fluoropyrazine (49.2 mg, 0.278 mmol), RuPhos (17.29 mg, 0.037 mmol), Pd(dba)2 (10.65 mg, 0.019 mmol) and Cs2CO3 (121 mg, 0.370 mmol) were combined in a vial. Toluene (0.842 ml) was added and the mixture was evacuated and back-filled with N2 three times. Heated under N2 at 80 C. overnight. The reaction was filtered through celite, rinsing with EtOAc. The filtrate was concentrated to give an orange gum. The crude sample was treated with conc. HCl/MeOH (1:10, 3 mL) at rt until the TBS group was cleaved. After concentration, the crude sample was purified by preparative HPLC (10% ACN/water to 90% ACN/water in ?40 min with 0.1% FA buffer) to give (R)-2-(5-fluoropyrazine-2-yl)-N-(6-(1-(1-hydroxypropan-2-yl)-1H-tetrazol-5-yl)pyridin-2-yl)-6-methoxy-1,2,3,4-tetrahydroisoquinoline-7-carboxamide (6 mg, 0.012 mmol, 6% yield).

In the field of chemistry, the synthetic routes of compounds are constantly being developed and updated. I will also mention this compound in other articles, 2-Bromo-5-fluoropyrazine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; Enanta Pharmaceuticals, Inc.; Granger, Brett; Wang, Guoqiang; Shen, Ruichao; He, Jing; He, Yong; Xing, Xuechao; Ma, Jun; Long, Jiang; Wang, Bin; Or, Yat Sun; (121 pag.)US2020/157095; (2020); A1;,
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Some tips on 875781-43-4

The synthetic route of 2-Bromo-5H-pyrrolo[2,3-b]pyrazine has been constantly updated, and we look forward to future research findings.

These common heterocyclic compound, 875781-43-4, name is 2-Bromo-5H-pyrrolo[2,3-b]pyrazine, its traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route. Recommanded Product: 875781-43-4

Step 1. (2-Bromo-5H-pyrrolo[2,3-b]pyrazine-5,7-diyl)dimethanol. To a stirred solution of 2-bromo-5H-pyrrolo[2,3-b]pyrazine (116.5 g, 589 mmol) in dioxane (1.75 L) was added dropwise aqueous NaOH (590 mL, 1175 mmol, 2 M) at room temperature, then formaldehyde (481 mL, 5884 mmol, 37% aqueous solution) was added to the mixture at room temperature. After that, the resulting mixture was stirred at room temperature for 18 hours. TLC (petroleum ether/EtOAc, 2:1) showed starting material was consumed completely. The three batches were combined for workup together. The reaction mixture was evaporated to remove most of solvent. The residue was neutralized with 2 M HCl and extracted with EtOAc (1 L¡Á3), the combined organic layers were washed water (1 mL) and brine (1 mL), dried over Na2SO4 and concentrated to dryness, which was triturated with MTBE to give (2-bromo-5H-pyrrolo[2,3-b]pyrazine-5,7-diyl)dimethanol (450 g, 95.5%) as a yellow solid.

The synthetic route of 2-Bromo-5H-pyrrolo[2,3-b]pyrazine has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Thorarensen, Atli; Brown, Matthew Frank; Casimiro-Garcia, Agustin; Che, Ye; Coe, Jotham Wadsworth; Flanagan, Mark Edward; Gilbert, Adam Matthew; Hayward, Matthew Merrill; Langille, Jonathan David; Montgomery, Justin Ian; Telliez, Jean-Baptiste; Unwalla, Rayomand Jal; US2015/158864; (2015); A1;,
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Analyzing the synthesis route of 19745-07-4

In the field of chemistry, the synthetic routes of compounds are constantly being developed and updated. I will also mention this compound in other articles, 2,5-Dichloropyrazine, other downstream synthetic routes, hurry up and to see.

Adding a certain compound to certain chemical reactions, such as: 19745-07-4, name is 2,5-Dichloropyrazine, belongs to Pyrazines compound, can increase the reaction rate and produce products with better performance than those obtained under traditional synthetic methods. Here is a downstream synthesis route of the compound 19745-07-4, Quality Control of 2,5-Dichloropyrazine

analogously to Synthesis Example 13, Step 1, starting with 2,5-dichloropyrazine: HPLC-MS: (m/z): 196.1 (M+H)+. 1-(6-Fluoropyrazin-2-yl)-1H-pyrazole-3-amine:

In the field of chemistry, the synthetic routes of compounds are constantly being developed and updated. I will also mention this compound in other articles, 2,5-Dichloropyrazine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; BAYER CROPSCIENCE AG; Heilmann, Eike Kevin; Greul, Joerg; Trautwein, Axel; Schwarz, Hans-Georg; Adelt, Isabelle; Andree, Roland; Luemmen, Peter; Hink, Maike; Adamczewski, Martin; Drewes, Mark; Becker, Angela; Voerste, Arnd; Goergens, Ulrich; Ilg, Kerstin; Jansen, Johannes-Rudolf; Portz, Daniela; US2015/239847; (2015); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Introduction of a new synthetic route about 58138-79-7

The synthetic route of 58138-79-7 has been constantly updated, and we look forward to future research findings.

Electric Literature of 58138-79-7,Some common heterocyclic compound, 58138-79-7, name is 2,6-Diiodopyrazine, molecular formula is C4H2I2N2, traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route.

An oven-dried sealed tube was charged with 2-bromo-4-methyl-thiazole- 5-carboxylic acid 4-fluoro-benzylamide (1.0 g, 3.03 mmol, 1.0 equiv). The sealed tube was purged with nitrogen and Rieke zinc (10 mL, 10 g of zinc in 100 mL of tetrahydrofuran) was added. The reaction was heated in the microwave oven for 15 min 50352at 100 0C. Stirring was stopped and the remaining zinc was allowed to settle. The supernatant containing the zinc reagent was transferred via syringe to a solution of 2,6- diiodopyrazine (704 mg, 2.1 mmol, 0.7 equiv), Pd(PPh3)4 (175 mg, 0.2 mmol, 5 mol%) in tetrahydrofuran (2 mL) and dimethyl formamide (0.1 mL). The reaction mixture was purged with nitrogen for 10 min, then stirred at 140 0C for 20 hr. After cooling, the solvent was removed in vacuo and the crude product was purified by column chromatography [SiO2, ethyl acetate/heptane, 10:90 to 40:60, v/v] to afford 2-(6-iodo- pyrazin-2-yl)-4-methyl-thiazole-5-carboxylic acid 4-fiuoro-benzylamide (100 mg, 7%). MS (M+H)+ = 455.1 , R1 = 1.53 min.

The synthetic route of 58138-79-7 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; NOVARTIS AG; NOVARTIS PHARMA GmbH; XENON PHARMACEUTICALS INC; WO2008/24390; (2008); A2;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Sources of common compounds: 6164-79-0

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 6164-79-0, its application will become more common.

Some common heterocyclic compound, 6164-79-0, name is Methyl 2-pyrazinecarboxylate, molecular formula is C6H6N2O2, traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route. Formula: C6H6N2O2

Methyl pyrazine-2-carboxylate (0.5g; 3.6mmol) was dissolved in THF (5mL), and 98% hydrazine (0.53mL; 11mmol) was added. The mixture was refluxed for 3h and cooled to rt. The resulting solid was filtered off, washed with THF and dried over P2O5 to give 0.28g (56%) of a white solid. Rf=0.53 (CHCl3/MeOH 10:1). mp 166-169C (lit. 167-169C) [64]. 1H NMR (300MHz, DMSO): delta 10.11 (s, 1H, NH), 9.12 (s, 1H, Ar), 8.82 (d, J=2.4Hz, 1H, Ar), 8.68 (d, J=2.4Hz, 1H, Ar), 4.65 (s, 2H, NH2). 13C NMR (75MHz, DMSO): delta 161.7, 147.4, 145.1, 143.7, 143.4.

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 6164-79-0, its application will become more common.

Reference:
Article; Hru?kova, Kate?ina; Pot??kova, Eli?ka; Hergeselova, Tereza; Liptakova, Lucie; Ha?kova, Pavlina; Mingas, Panagiotis; Kova?ikova, Petra; ?im?nek, Toma?; Vavrova, Kate?ina; European Journal of Medicinal Chemistry; vol. 120; (2016); p. 97 – 110;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Share a compound : 54608-52-5

According to the analysis of related databases, 54608-52-5, the application of this compound in the production field has become more and more popular.

Each compound has different characteristics, and only by selecting the characteristics of the compound suitable for a specific situation can the compound be applied on a large scale. 54608-52-5, name is 2-Hydrazinopyrazine, This compound has unique chemical properties. The synthetic route is as follows., Computed Properties of C4H6N4

General procedure: 2.5. General preparation of dregamine andtabernaemontanine derivatives 3-12Dregamine/tabernaemontanine (1/2) (1 equiv.) was dissolved in MeOH (3 mL) with the suitablehydrazine/hydroxylamine (3 equiv.) and a catalytic amount of acetic acid. Themixture was stirred under reflux for 2-24 h. The reaction mixture was extractedwith EtOAc (3 x 50 mL). The organic layers were combined and dried (Na2SO4).The solvent was removed under vacuum at 40 C and the obtained residue waspurified by column chromatography 2.5.6. Tabernaemontanine pyrazine-2-ylhydrazone(8) Obtained from reaction of the compound 2 with 2-hydrazinopyrazine(Sigma-Aldrich Chemie GmbH, Riedstrasse D-89555, Steinhelm, Germany; 3 equiv).The mixture was left under reflux for 24 h. The residue was purified by flashcolumn chromatography (silica gel CH2Cl2/MeOH 1:0 to93:7) to afford 10 mg (0.022 mol, yield 36 %) of an amorphous orange powder. IR(NaCl) vmax 3526,1730, 1656 cm-1.1H NMR (400 MHz, MeOD) delta 9.15 (1H, s, H-3?), 8.67 (1H, bs, H-6?),8.51 (1H, bs, H-5?), 8.16 (1H, d, J = 8.0 Hz, H-9), 8.03 (1H, bs, N-H), 7.93 (1H, d, J = 8.0Hz, H-12), 7.80 (1H, t, J = 7.8 Hz, H-11), 7.66 (1H, t, J = 7.6Hz, H-10), 4.55 (1H, td, J = 8.0, 3.0 Hz, H-5), 3.84 (2H, m, H-6), 3.60(3H, m, H-14, H-15), 3.50 (2H, m, H-16, H-21a), 3.21 (3H, s, -COOMe),3.11 (3H, s, N-Me), 2.33 (2H, m, H-19), 2.19 (1H, m, H-21b), 2.10 (1H, m,H-20), 1.62 (3H, t, J = 7.3 Hz, H-18) ppm; 13C NMR (101 MHz,MeOD) delta 173.2 (-COOMe), 155.5 (C-3), 153.9 (C-2?), 142.7 (C-6?), 141.8(C-5?), 138.0 (C-13), 134.3 (C-3?), 131.0 (C-8), 124.6 (C-11), 119.9 (C-10),119.7 (C-9), 115.2 (C-7), 111.7 (C-12), 59.3 (C-5), 50.9 (-COOMe), 46.8(C-21), 43.6 (N-Me), 43.0 (C-20), 42.9 (C-16), 34.0 (C-15), 32.2 (C-14), 26.5(C-19), 19.4 (C-6), 13.1 (C-18) ppm. HRMS-ESI-TOF m/z calcd C25H30N6O2[M+H] + 447.2430, found 447.2510.

According to the analysis of related databases, 54608-52-5, the application of this compound in the production field has become more and more popular.

Reference:
Article; Paterna, Angela; Borralho, Pedro M.; Gomes, Sofia E.; Mulhovo, Silva; Rodrigues, Cecilia M.P.; Ferreira, Maria-Jose U.; Bioorganic and Medicinal Chemistry Letters; vol. 25; 17; (2015); p. 3556 – 3559;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem