Pyrazines

Reference of 446286-90-4, In the next few decades, the world population will flourish. As the population grows rapidly and people all over the world use more and more resources, all industries must consider their environmental impact. 446286-90-4, name is 2-Bromo-5-(piperazin-1-yl)pyrazine belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below.

A mixture of 2-bromo-5-(piperazin-1-yl)pyrazine (458 mg, 1.88 mmol), 2-iodopropane (479 mg, 2.82 mmol) and K2C03 (518 mg, 3.76 mmol) in MeCN (10 mL) was stirred at 60 C overnight. Concentrated and purified by silica gel column (MeOH/EA = 1:10) to give the titleproduct (388 mg, yield 72%). MS (ES+) C11H17BrN4 requires: 284, found: 285[M+H].

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-(piperazin-1-yl)pyrazine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; BLUEPRINT MEDICINES CORPORATION; BROOIJMANS, Natasja; BRUBAKER, Jason, D.; FLEMING, Paul, E.; HODOUS, Brian, L.; KIM, Joseph, L.; WAETZIG, Josh; WILLIAMS, Brett; WILSON, Douglas; WILSON, Kevin, J.; (347 pag.)WO2017/181117; (2017); A1;,
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. 875781-43-4, name is 2-Bromo-5H-pyrrolo[2,3-b]pyrazine, A new synthetic method of this compound is introduced below., HPLC of Formula: C6H4BrN3

A method for preparing methyl (5-tosyl-5H-pyrrolo[2,3-b]pyrazin-2-yl)carbamate, comprising the steps of: (1) using 5-bromo-4,7-diazaindene as raw material,Reacting with the prepared 20% ammonia water at a temperature of 140 C and a pressure of 3 MPa,The molar ratio of 5-bromo-4,7-diazaindene to ammonia water is 1:12. A cuprous chloride/ferrous chloride composite catalyst is added to the reaction system, and the molar ratio of cuprous chloride to ferrous chloride is 1:1, and the total amount of the catalyst is2% by mass of 5-bromo-4,7-diazepine, the reaction gives compound 1;

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:
Patent; Nanjing Xin Meihe Pharmaceutical Technology Co., Ltd.; Zhou Wenbin; Yang Yuanming; Wang Zhengxi; (6 pag.)CN110105363; (2019); A;,
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. 25911-65-3, name is 3-Aminopyrazine-2-carbonitrile, A new synthetic method of this compound is introduced below., Safety of 3-Aminopyrazine-2-carbonitrile

c) 4-Amino-2-[(4-methoxyphenoxy)methyl]pteridine Obtained using the procedure described in section c of Example 2, starting with 9.8 g (0.082 mole) of 3-amino-2-pyrazinecarbonitrile and the above solution of 2-(3-methoxyphenoxy)acetamidine in absolute ethanol. Refluxing time: 2 hours. Yld: 5.5 g (24%), m.p. 238-240 C. (ethanol/N,N-dimethylformamide). NMR (DMSO-d6): delta=3.7 (3H, s); 5.0 (2H, s); 6.9 (4H, s); 8.3 (2H, peak exchangeable with CF3 COOD); 8.8 (1H, d); 9.0 (1H, d).

The synthetic route of 25911-65-3 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Lipha, Lyonnaise Industrielle Pharmaceutique; US5167949; (1992); A;,
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. 51171-02-9, name is Methyl 3-Bromo-2-pyrazinecarboxylate, This compound has unique chemical properties. The synthetic route is as follows., Quality Control of Methyl 3-Bromo-2-pyrazinecarboxylate

(B) Methyl 2-phenylamino-3-pyrazine carboxylate A mixture of 9.5 g. of methyl 2-bromo-3-pyrazine carboxylate, 8.2 g. of aniline, 0.5 g. of p-toluene sulfonic acid and 100 ml. of water is stirred and refluxed for two hours. The reaction mixture is poured on ice, extracted with ethyl acetate, the organic extracts are dried and concentrated to yield an oil. The crude residue is eluted on a silica gel column with ethylacetate-hexane (1:2) yielding the product of this example as a yellow solid, m.p. 72-75 C.

Chemical properties determine the actual use. Each compound has specific chemical properties and uses. We look forward to more synthetic routes in the future to expand reaction routes of 51171-02-9.

Reference:
Patent; Schering Corporation; US4492702; (1985); A;,
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. 59489-71-3, name is 2-Amino-5-bromopyrazine, A new synthetic method of this compound is introduced below., COA of Formula: C4H4BrN3

Step 1: 2-amino-5-cyanopyrazine. To a stirred solution of 5-bromo-2-aminopyrazine (1.0 g) 5.8 mmol), CuI (2.76 g, 14.5 mmol), 18-crown-6 (121 mg; 0.46 mmol), potassium cyanide (943 mg; 14.5 mmol) in dimethylformamide (20 mL) was added Pd(PPh3)4 (196 mg; 0.17 mmol). After stirring at room temperature for 20 minutes the reaction was placed in an oil bath at 155 C. for 2 hours. The reaction was allowed to cool to room temperature and then poured into chloroform (300 mL). A precipitate formed that was filtered and triturated with hexanes to yield an off white solid (60% yield).

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:
Patent; Keegan, Kathleen S.; Kesicki, Edward A.; Gaudino, John Joseph; Cook, Adam Wade; Cowen, Scott Douglas; Burgess, Laurence Edward; US2003/69284; (2003); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 109838-85-9, As we all know, there are many different methods for the synthesis of a compound, and people can choose the synthesis method that suits their own laboratory according to the actual situation. 109838-85-9 name is (R)-2-Isopropyl-3,6-dimethoxy-2,5-dihydropyrazine, This compound is widely used in many fields, so it is necessary to find a new synthetic route. The downstream synthesis method of this compound is introduced below.

[0562] A solution of compound 4-01-5 (8.9 g, 48 mmol) in tetrahydrofuran (100 mL) was cooled to -70C and n-butyl lithium (2.5 M, 19.5 mL, 49 mmol) was added under nitrogen while the temperature was kept below -70C. A solution of compound 7- bromohept-l-ene (8.0 g, 45 mmol) in tetrahydrofuran (15 mL) was added at -70C. The reaction mixture was stirred at -70C for 2 hours, then slowly heated to 20C and stirred for 1 hour. The reaction mixture was poured into saturated ammonium chloride solution (50 mL) and extracted with ethyl acetate (200 mL *2). The combined organic phase was washed with brine (100 mL*2), dried over anhydrous sodium sulfate, and concentrated in reduced pressure. The residue was purified by column chromatography (petroleum ether to petroleum ether: ethyl acetate = 50: 1) to afford compound 4-01-6 (7 g, 55% yield) as a colorless oil.

At the same time, in my other blogs, there are other synthetic methods of this type of compound, (R)-2-Isopropyl-3,6-dimethoxy-2,5-dihydropyrazine, and friends who are interested can also refer to it.

Reference:
Patent; CORNELL UNIVERSITY; TRI-INSTITUTIONAL THERAPEUTICS DISCOVERY INSTITUTE; LIN, Gang; NATHAN, Carl; KIRKMAN, Laura; ZHAN, Wenhu; MORGAN, Trevor; SATO, Kenjiro; HARA, Ryoma; KAWASAKI, Masanori; IMAEDA, Toshihiro; TOITA, Akinori; OKAMOTO, Rei; YUKAWA, Takafumi; ASO, Kazuyoshi; WONG, Tzu-Tshin; GINN, John, D.; FOLEY, Michael, A.; (296 pag.)WO2019/75259; (2019); A1;,
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. 33332-28-4, name is 2-Amino-6-chloropyrazine, A new synthetic method of this compound is introduced below., Quality Control of 2-Amino-6-chloropyrazine

EXAMPLE 3 N-(6-Chloro-pyrazin-2-yl)-2,6-dimethyl-4-hydroxy-2H-1,2-benzothiazine-3-carboxamide-1,1-dioxide 2.0 g (7 mmols) of methyl 2,6-dimethyl-4-hydroxy-2H-1,2-benzothiazine-3-carboxylate-1,1-dioxide and 1.1 g (8.4 mmols) of 2-amino-6-chloro-pyrazine were reacted in 150 ml of xylene analogous to Example 2, and the reaction product was isolated and recrystallized from ethylene chloride. 2.1 g (79percent of theory) of N-(6-chloro-pyrazin-2-yl)-2,6-dimethyl-4-hydroxy-2H-1,2-benzothiazine-3-carboxamide-1,1-dioxide were obtained. Melting point: 296°-298° C. 1H-NMR (CDCl3 +d-TFA): delta=9.55 (s, 1,3′-H); 8.55 (s, 1,5′-H); 8.05-7.55 (m, 3,5-H, 7-H, 8-H); 3.00 (s,3,N-CH3); 2.60 (s,3,CH3).

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:
Patent; Dr. Karl Thomae Gesellschaft mit beschrankter Haftung; US4533664; (1985); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 33332-25-1,Some common heterocyclic compound, 33332-25-1, name is Methyl 5-chloropyrazine-2-carboxylate, molecular formula is C6H5ClN2O2, 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 35-Chloropyrazine-2-carboxylic acidFehler. Es ist nicht moglich, durch die Bearbeitung von Feldfunktionen Objekte zu erstellen. Methyl 5-chloropyrazine-2-carboxylate (CAS [33332-25-1], 1 g, 5.79 mmol) was dissolved in a mixture of THF (50 ml) and water (50 ml). Lithium hydroxide monohydrate (243 mg, 5.79 mmol) was added and the reaction mixture was stirred at RT overnight. The pH was adjusted to 1 with 1M HC1 and the product was extracted with three portions of EtOAc. The combined organic layers were dried over Na2S04 and concentrated under vacuum. The crude material was purified by flash chromatography (Si02, 50 g, 0 to 20% MeOH in DCM) to yield the title compound as white solid (741 mg, 81%). MS (ISP): m/z = 159.0 [M+H]+.

The synthetic route of 33332-25-1 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; F. HOFFMANN-LA ROCHE AG; BORRONI, Edilio; GOBBI, Luca; HILPERT, Hans; HONER, Michael; MURI, Dieter; NARQUIZIAN, Robert; POLARA, Alessandra; WO2012/168175; (2012); A1;,
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. 41110-28-5, name is 3-Methylpyrazine-2-carboxylic acid, This compound has unique chemical properties. The synthetic route is as follows., COA of Formula: C6H6N2O2

In a 2-E flask, 3-methylpyrazine-2-carboxylic acid (Matrix, 19.95 g, 144 mmol) was suspended in MeOH (500 mE). The suspension was cooled in an ice-water bath, and concentrated sulfuric acid (Fluka, 27.3 mE, 506 mmol) was added over a time period of 5 mm. The reaction mixture was heated to 80 C. for 5 h. The reaction mixture was concentrated under reduced pressure and the residue was taken up in DCM (750 mE). The excess acid was neutralized careffilly with aqueous NaOH (SM, 200 mE). The aqueous layer was separated and extracted with DCM (250 mE). The combined organic layers were combined, dried over Mg504 and concentrated to afford the title compound (16.15 g, 106 mmol, 73%). MS mlz=153 (M+H).

Chemical properties determine the actual use. Each compound has specific chemical properties and uses. We look forward to more synthetic routes in the future to expand reaction routes of 41110-28-5.

Reference:
Patent; WHITE, Ryan; ALLEN, Jennifer R.; EPSTEIN, Oleg; HONG, Fang-Tsao; HUA, Zihao; HUMAN, Jason Brooks; LOPEZ, Patricia; OLIVIERI, Philip R.; ROMERO, Karina; SCHENKEL, Laurie; STELLWAGEN, John; TAMAYO, Nuria A.; ZHENG, Xiao Mei; US2014/213581; (2014); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem