Pyrazines

Reference of 486460-21-3,Some common heterocyclic compound, 486460-21-3, name is 3-(Trifluoromethyl)-5,6,7,8-tetrahydro-[1,2,4]triazolo[4,3-a]pyrazine, molecular formula is C6H7F3N4, 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.

phosgene(725 mg, 9.2 mmol) and 1- (2,3-bis (4-fluorophenoxy) benzoic acid methyl ester in the presence of methylene chloride, 6-nitrophenyl) piperazine crude (1.213g, 5.0mmol) in the mixture, the temperature below 0 C, 10min added, maintained at 0 C reaction lh, the direct response to the next step . To the above reaction solution was added 3- (trifluoromethyl) -5,6,7,8-tetrahydro- [1,2,4] triazolo [4,3-a] pyrazine (800 mg, And triethylamine (842 mg, 8.4 mmol). The temperature of the reaction system was raised to room temperature and stirred for 20 h. The reaction was quenched by the addition of 20 ml of saturated sodium bicarbonate solution and extracted with dichloromethane (20 ml of X2). The organic phases were combined, dried over anhydrous sodium sulfate, filtered, concentrated and purified by column chromatography (petroleum ether: ethyl acetate = 3: 2) Yellow solid 1.345 g, 52.1% yield in three steps.

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 3-(Trifluoromethyl)-5,6,7,8-tetrahydro-[1,2,4]triazolo[4,3-a]pyrazine, its application will become more common.

Reference:
Patent; Shanghai Institute Of Pharmaceutical Industry; China State Institute of Pharmaceutical Industry; Meng, Xiangguo; Cai, Zhengyan; Zhou, Weicheng; Jiang, Jingzhang; Zhu, Yijun; Ge, Yuanyuan; Yan, Pingping; (32 pag.)CN103172635; (2016); B;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

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. 117719-17-2, name is 5-Bromo-3-morpholinopyrazin-2-amine, A new synthetic method of this compound is introduced below., name: 5-Bromo-3-morpholinopyrazin-2-amine

A mixture of Intermediate 1-02 (8.17 g, 31.52 mmol) and 1,3-dichloroacetone (6.0 g, 47.29 mmol) in 2-propanol (15 mE) was heated in a sealed tube at 55 C. for 2 days. Oncooling, the mixture was filtered and rinsed with Et20 and MeOR. The solid was purified by flash chromatography on silica gel (MeOH:DCM, 5:95) and the product obtained was washed with MeOR and dried to give Intermediate 1-57(3.97 g, 38%).

The synthetic route of 117719-17-2 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; CENTRO NACIONAL DE INVESTIGACIONES ONCOLOGICAS (CNIO); Serrano Marugan, Manuel; Pastor Fernandez, Joaquin; Martinez Gonzalez, Sonia; Ortega Molina, Ana; Bischoff, James R.; Oyarzabal Santamarina, Julen; (220 pag.)US9993554; (2018); B2;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 27398-39-6, The chemical industry reduces the impact on the environment during synthesis 27398-39-6, name is 3-Chloropyrazine-2-carboxylic acid, I believe this compound will play a more active role in future production and life.

General procedure: A total of 0.3 g of 3-Cl-POA (1.9 mmol) was dispersed in dry toluene with thionyl chloride(0.4 mL, 5.7 mmol, 3 equiv.) and 1?2 drops of N,N-dimethylformamide (DMF) as a catalyst. Thereaction mixture was stirred and heated in a round bottom flask in an oil bath under a condenser,at 95°C for 1 h. The solvent was evaporated in vacuo and the residue was azeotroped with dry toluene(3 20 mL). The acyl chloride was used for the following step, without purification. The whole amount of the 3-chloropyrazine-2-carbonyl chloride prepared in the previousstep was dissolved in dry acetone. An appropriate benzylamine (5.7 mmol, 3 equiv., with respect to the starting acid), along with triethylamine (1.9 mmol, 1 equiv.), were added to thereaction mixture and stirred at laboratory temperature overnight. The progress of the reactionwas checked by TLC in system hexane/ethyl acetate (1:1 or 2:1). The reaction mixture wasadsorbed to silica by removing the solvents in vacuo and the product was purified by flashchromatography using gradient elution with ethyl acetate in hexane. For compounds 1?3,corresponding N-benzyl-3-(benzylamino)pyrazine-2-carboxamides 1a?3a were formed simultaneouslyin a molar ratio of approximately 2:3, with an excess of 1a?3a. Rf in hexane/ethyl acetate 1:1 mobilephase: 1a?0.85, 1?0.49, 2a?0.84, 2?0.51, 3a?0.71, and 3?0.40. After flash-chromatography,compounds 2, 2a, 3, 3a, 4, 8, and 13 were recrystallized from EtOH/H2O.

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, 3-Chloropyrazine-2-carboxylic acid, other downstream synthetic routes, hurry up and to see.

Reference:
Article; Semelkova, Lucia; Jand’ourek, Ond?ej; Kone?na, Klara; Paterova, Pavla; Navratilova, Lucie; Trejtnar, Franti?ek; Kubi?ek, Vladimir; Kune?, Ji?i; Dole?al, Martin; Zitko, Jan; McPhee, Derek J.; Molecules; vol. 22; 3; (2017);,
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Pyrazine | C4H4N2 – PubChem

Application of 33332-28-4,Some common heterocyclic compound, 33332-28-4, name is 2-Amino-6-chloropyrazine, molecular formula is C4H4ClN3, 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.

EXAMPLE 4A 6-(allyloxy)-2-pyrazinamine A mixture of allyl alcohol (0.21 mL, 3.08 mmol) in dioxane (4 mL) was treated with NaH (60percent, 3.08 mmol), stirred for 30 minutes, treated with 2-amino-6-chloropyrazine (200 mg, 1.54 mmol), heated to 140° C. in a Smith Synthesizer for 2200 seconds, and filtered. The filtrate was concentrated and purified by flash column chromatography eluding with hexanes/ethyl acetate (2:1) to provide the desired product (133 mg, 57percent). MS (DCI/NH3) m/z 152.0 (M+H)+; 1H NMR (500 MHz, CD2Cl2) delta 4.75 (m, 2H), 5.24 (m, 1H), 5.37 (m, 1H), 6.05 (m, 1H), 7.50 (s, 1H), 7.53 (s, 1H).

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 2-Amino-6-chloropyrazine, its application will become more common.

Reference:
Patent; Tao, Zhi-Fu; Lin, Nan-Horng; Wang, Le; Sowin, Thomas J.; US2005/96324; (2005); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 939412-86-9, The chemical industry reduces the impact on the environment during synthesis 939412-86-9, name is (3-Chloropyrazin-2-yl)methanamine hydrochloride, I believe this compound will play a more active role in future production and life.

To a solution of l-((benzyloxy)carbonyl)-2-cyanopiperidine-4-carboxylic acid (30 mg, 0.104 mmol) in anhydrous DCM (5 mL) was added HATU (43.5 mg, 0.114 mmol), Et3N (31.56 mg, 0.312 mmol) and (3-chloropyrazin-2-yl)methanamine hydrochloride (20.5 mg, 0.114 mmol). The reaction mixture was stirred at 13 C for 12 hrs. The reaction was quenched by the addtion of water (10 mL), then it was extracted with DCM (10 mL x 3), the combined organic layers were washed with brine (10 mL), dried over sodium sulfate, filtered and concentrated to afford the crude product ,which was purified on silica gel column chromatograph (PE/THF = 100% ~ 50 %) to give benzyl 4-(((3-chloropyrazin-2-yl)methyl)carbamoyl)-2-cyanopiperidine- 1 -carboxylate (40 mg, yeild 93%) .1H NMR (400MHz, METHANOL-d4) delta= 8.54 (d, J=2.5 Hz, 1H), 8.35 (d, J=2.5 Hz, 1H), 7.44 – 7.31 (m, 5H), 5.53 (d, J=4.0 Hz, 1H), 5.21 (d, J=2.5 Hz, 2H), 4.64 (s, 2H), 4.25 (d, J=13.1 Hz, 1H), 2.87 – 2.84 (m, 1H), 2.88 – 2.77 (m, 3H), 2.16 (d, J=12.5 Hz, 1H), 2.02 – 1.91 (m, 2H), 1.66 (dq, J=4.8, 12.9 Hz, 1H).

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, (3-Chloropyrazin-2-yl)methanamine hydrochloride, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; MERCK SHARP & DOHME CORP.; WU, Hao; KIM, Ronald M.; LIU, Jian; GAO, Xiaolei; BOGA, Sobhana Babu; GUIADEEN, Deodialsingh; KOZLOWSKI, Joseph; YU, Wensheng; ANAND, Rajan; YU, Younong; SELYUTIN, Oleg B.; GAO, Ying-Duo; LIU, Shilan; YANG, Chundao; WANG, Hongjian; WO2014/114185; (2014); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

89180-45-0, name is 5-Chloro-2-hydroxypyrazine, belongs to pyrazines compound, is considered to be a conventional heterocyclic compound, which is widely used in drug synthesis. The chemical synthesis route is as follows. Product Details of 89180-45-0

A mixture of 2-hydroxy-5-chloropyrazine in POCl3 (21 equiv.) was heated at 1200C for 2 h. The reaction mixture was cooled and poured on ice and extracted with dichloromethane. The organic solvent was collected, dried over Na2SO4 and filtered. The solvent was filtered over silica gel followed by ethyl acetate. The solvents were evaporated to provide the title compound

The synthetic route of 89180-45-0 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; MERCK FROSST CANADA LTD.; WO2008/46226; (2008); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 21279-62-9, name is 3-Chloropyrazine-2-carboxamide, 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 21279-62-9, Product Details of 21279-62-9

General procedure: Compounds 1-6 were prepared according to conventional organic synthesis methods. 3-Chloropyrazine-2-carboxamide (1.27 mmol) was dissolved in THF (20 mL) in a round bottom flask and after that treated with two equivalents of the corresponding benzylamine and an equimolar amount of triethylamine. The reaction was conducted with continuous stirring and heating (70 C) under reflux in an oil bath for 15 h. Compounds 7-15 were synthesised using a microwave reactor with a focused field. 3-Chloropyrazine-2-carboxamide (1.27 mmol) was put into a thick-walled tube together with the corresponding benzylamine (2.54 mmol), pyridine (1.27 mmol), methanol (approx. 5 mL) and a magnetic stir bar and then sealed with a special cap. The reaction parameters were set according to the previously published paper as follows-140 C, 30 min, 200 W [29]. Reaction progress was checked by TLC (hexane:ethyl acetate-1:1). Regardless of the synthesis method used,all reaction mixtures were adsorbed on silica and subjected to preparative flash chromatography (hexane and ethyl acetate, gradient elution, detection wavelengths 260 nm and 280 nm). Products were recrystallized from ethanol or ethanol and water if necessary. All final substances were chemically characterized (1H-NMR, 13C-NMR, IR, melting point and elemental analysis).

At the same time, in my other blogs, there are other synthetic methods of this type of compound, 3-Chloropyrazine-2-carboxamide, and friends who are interested can also refer to it.

Reference:
Article; Jandourek, Ondrej; Tauchman, Marek; Paterova, Pavla; Konecna, Klara; Navratilova, Lucie; Kubicek, Vladimir; Holas, Ondrej; Zitko, Jan; Dolezal, Martin; Molecules; vol. 22; 2; (2017);,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

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., HPLC of Formula: C4H6N4

General procedure: p-methylbenzenesulfonic acid (1.7 mg, 0.01 mmol) was added to pyrrole-2-carboxaldehyde derivative 3a (50 mg, 0.406 mmol) and 1-(pyrazin-2-yl)hydrazine (44.7 mg, 0.406 mmol) in 1,2-dichloroethane (50 mL). The reaction mixture was refluxing for 4 h. Then, 0.5 ml of NEt3 was added into the mixture. The reaction mixture was stirred for 10 minutes before subsequent addition of BF3*OEt2 (0.5 mL), and the reaction was left stirring at refluxing condition for 4 h. After cooling to room temperature, the reaction mixture was added CH2Cl2 (50 mL) and poured into water (50 mL). The organic phase was isolated and the corresponding water phase was extracted twice with CH2Cl2 (30 mL). Organic layers were combined, washed with water, dried over anhydrous sodium sulfate, filtered. After solvent removal by evaporation, the crude product was purified by silica gel column chromatography (CH2Cl2/n-hexane = 2:1) to afford 2a (51.7 mg, 41%) as yellow solids.

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; Jiang, Xindong; Yue, Shuai; Chen, Kepeng; Shao, Zhumei; Li, Chen; Su, Yajun; Zhao, Jianzhang; Chinese Chemical Letters; vol. 30; 12; (2019); p. 2271 – 2273;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 1196152-38-1,Some common heterocyclic compound, 1196152-38-1, name is 2-Bromo-5-(trifluoromethyl)pyrazine, molecular formula is C5H2BrF3N2, 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.

[((1R,4S,6R)-3-{[6-methyl-3-(2-pyrimidinyl)-2-pyridinyl]carbonyl}-3-azabicyclo[4.1.0]hept-4-yl)methyl]amine D25 (80 mg) and 2-bromo-5-(trifluoromethyl)pyrazine (67.4 mg, 0.297 mmol) were dissolved in DMF (2 ml) then sodium carbonate (52.4 mg, 0.495 mmol) was added and the mixture was heated to 50 C. for 2 hours. DMF was evaporated under vacuum and the residue was dissolved in DCM (4 ml) and washed with NaHCO3 saturated solution (4 ml). The organic phase was filtered through a phase separator tube, concentrated under vacuum and the resulting crude product was purified by SCX Chromatography (column size 5 g). Another purification was performed by silica -NH chromatography (Biotage SP-column size 25 g using Cy_EtOAc=5:5 to EtOAc as eluent). It was recovered the title compound E45 (30 mg). UPLC: (Acid Final_QC): rt=0.78 and 0.79 minutes (two rotamers), peaks observed: 470 (M+1). C23H22F3N7O requires 469. 1H NMR (400 MHz, DMSO-d6) delta ppm 8.91-8.82 (m, 2H), 8.36 (d, 1H), 8.20-7.86 (m, 3H), 7.47 (t, 1H), 7.36 (d, 1H) 4.40 (d, 1H), 3.81-3.55 (m, 2H), 3.49-3.35, (m, 2H), 2.38-2.30 (br. s., 3H), 1.80-1.65 (m, 2H), 1.15-1.06 (m, 1H), 1.03-0.91 (m, 1H), 0.80-0.71 (m, 1H), 0.29-0.19 (m, 1H).

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 2-Bromo-5-(trifluoromethyl)pyrazine, its application will become more common.

Reference:
Patent; ALVARO, Giuseppe; Amantini, David; Castiglioni, Emiliano; Di Fabio, Romano; Pavone, Francesca; US2010/144760; (2010); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 110223-15-9, 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. 110223-15-9, name is 2-Amino-3-benzyloxypyrazine, This compound has unique chemical properties. The synthetic route is as follows.

General procedure: For aromatic urea derivatives; the appropriate aromatic isocyanate(3.0 mmol) was added to a solution of the appropriate 2-amino-3-benzyloxy pyrazine derivative (2.5 mmol) in THF(10 mL). The reaction was refluxed for 3e6 h. After cooling, thereaction mixture was evaporated and the residue was purified byprecipitation in cold methanol and filtered to give the targetcompound(s). For aliphatic urea derivatives; the appropriatealiphatic isocyanate derivative (1.02 mmol) was added to a solutionof the appropriate 2-amino-3-benzyloxy pyrazine derivative(0.85 mmol) in dry THF (5 mL) in the presence of NaH (60% inmineral oil, 68 mg, 1.71 mmol). The reaction was refluxed for 5 h.After cooling, the reaction mixture was evaporated and the residuewas purified by flash column chromatography (SiO2, EA/n-Hex 1/4).

The chemical industry reduces the impact on the environment during synthesis 2-Amino-3-benzyloxypyrazine. I believe this compound will play a more active role in future production and life.

Reference:
Article; Elkamhawy, Ahmed; Park, Jung-eun; Hassan, Ahmed H.E.; Pae, Ae Nim; Lee, Jiyoun; Paik, Sora; Park, Beoung-Geon; Roh, Eun Joo; European Journal of Medicinal Chemistry; vol. 157; (2018); p. 268 – 278;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem