Category: Pyrazines

55557-52-3, The chemical industry reduces the impact on the environment during synthesis 55557-52-3, name is 3-Chloropyrazine-2-carbonitrile, I believe this compound will play a more active role in future production and life.

Into a vessel containing 50 mL ethanol was added 1.0 g of 3-chloropyrazine-2- carbonitrile (Exp-5-g22, 7.2 mmol), 1.1 g PMBNHNH2 (7.3 mmol) and 1.9 g K2C03 (14.2 mmol). The reaction mixture thus provided was heated to reflux and refluxing was continued for 6 hours, then the mixture was cooled to ambient temperature, filtered and the solid was washed sequentially with 10 mL H20 and 10 mL of methanol and dried yielding 1.0 g Exp-5-g23 (calculated yield 56%).

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

Reference:
Patent; MERCK SHARP & DOHME CORP.; LIVERTON, Nigel; JONES, Philip; LEI, Zhiyu; LIU, Fuqing; LUO, Yunfu; DONG, Jingchao; SOLL, Richard; WO2013/63100; (2013); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

875781-43-4, 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.

Step 1 To 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 HCl and extracted with EtOAc (2*). 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*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.

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 875781-43-4.

Reference:
Patent; Hendricks, Robert Than; Hermann, Johannes; Kondru, Rama; Lou, Yan; Lynch, Stephen M.; Owens, Timothy D.; Soth, Michael; US2011/230462; (2011); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Some common heterocyclic compound, 27825-20-3, name is Methyl 3-Hydroxy-2-pyrazinecarboxylate, molecular formula is C6H6N2O3, 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. 27825-20-3

EXAMPLE 19 In 5 mL of dimethyl sulfoxide is dissolved 0.42 g of L-alanyl-L-alanine trifluoroacetate. Then, 1.07 mL of triethylamine and 0.71 g of methyl 3-hydroxy-2-pyrazinecarboxylate are successively added to the solution, which is then stirred at 40 C. for 17 hours. The solvent is distilled off under reduced pressure, and 2 mL of water was added to the residue thus obtained. The deposited product is collected by filtration and purified by column chromatography [eluent: chloroform:methanol =30:1) to obtain 0.035 g of (2S)-2-[((2S)-2-{[(3-oxo-3,4-dihydro-2-pyrazinyl)carbonyl]amino}-propanoyl)amino]propanoic acid. IR(KBr) cm-1: 1665, 1675, 1655 NMR(DMSO-d6) delta value: 1.28(3H,d,J=7 Hz), 1.32(3H,d,J=7 Hz), 3.95-4.95(2H,m), 5.1(2H,brs), 7.71(1H,d,J=3 Hz), 7.87(1H,d,J=3 Hz), 8.32(1H,d,J=7 Hz), 9.9(1H,brs)

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 27825-20-3, its application will become more common.

Reference:
Patent; Furuta, Yousuke; Egawa, Hiroyuki; Nomura, Nobuhiko; US2002/13316; (2002); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

122-05-4,Some common heterocyclic compound, 122-05-4, name is Pyrazine-2,5-dicarboxylic acid, molecular formula is C6H4N2O4, 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.

Pyrazine-2,5-dicarboxylic acid (900 mg, 5.35 mmol) was dissolved in MeOH (9 mL) and Hydrogen chloride ~1.25M solution in Methanol (9 mL) was added. Then the mixture was heated to 50 C and stirred at that temperature for 8 hrs. Then it was left stirring at RT overnight. The day after 2 mL more of HCI ~1.25 M in MeOH was added and the mixture heated to 50 C and stirred at that temperaure for further 1 h. The mixture was cooled down to RT and concentrated under reduced pressure affording 2,5-dimethyl pyrazine-2,5- dicarboxylate (p139, 949 mg, y= 90%). MS (m/z): 197.1 [MH]+.

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route Pyrazine-2,5-dicarboxylic acid, its application will become more common.

Reference:
Patent; INDIVIOR UK LIMITED; CREMONESI, Susanna; MICHELI, Fabrizio; SEMERARO, Teresa; TARSI, Luca; (364 pag.)WO2016/67043; (2016); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

24241-18-7, 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 24241-18-7 as follows.

Step 1 A 500 ml three necked round bottom flask was charged with 3,5-dibromopyrazine-2- amine (25.0 g, 0.0988 mole) which was dissolved in acetonitrile (250 ml). The reaction mixture was cooled to 0 C and triethylamine (50.0 g, 0.4941 mole), copper (1) iodide (2.26 g, 0.0119 mole), and Pd (PPh3)4 (5.7 g, 0.0049 mole) were added under nitrogen atmosphere. The reaction mixture was stirred for 10 min at 0 C followed by slow addition of trimethylsilylacetylene (10.7g, 0.1089 mole) over 15 min at the same temperature. After completion of the addition, the reaction mixture was warmed up to RT and stirred for 90 min. The reaction mixture was diluted by ethyl acetate and filtered. The filtrate was collected and washed with water. Layers were separated and aqueous layer was re-extracted by ethyl acetate. Combined organic layer was dried over Na2S04, filtered and concentrated to afford crude product which was purified using column purification to afford 20.0 g of 5-bromo-3-((trimethylsilyl)ethynyl)pyrazine-2-amine.

According to the analysis of related databases, 2-Amino-3,5-dibromopyrazine, the application of this compound in the production field has become more and more popular.

Reference:
Patent; PRINCIPIA BIOPHARMA INC.; GOLDSTEIN, David, Michael; BRAMELD, Kenneth, Albert; OWENS, Tim; WO2014/81732; (2014); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

These common heterocyclic compound, 24241-18-7, name is 2-Amino-3,5-dibromopyrazine, 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. 24241-18-7

2-chloroacetaldehyde (0.79 g, 4 mmol) was slowly added to a freshly prepared solution of 3,5-dibromopyrazin-2-amine (1) (0.51 g, 2 mmol) in 2-propanol (20 mL). The mixture was stirred at reflux under a nitrogen atmosphere for 24 h. After cooling, CH2Cl2 (25 mL) and Et3N (1 mL) were added to the reaction solution. Thereafter, the solvent was evaporated under reduced pressure, and then the residue was washed with 11 mL mixed solution (water: 2-propanol = 10:1) for 2 times, filtered and dried under vacuum to give 6,8-dibromoimidazo[1,2-a]pyrazine (2) as a brown solid, which was pure enough to be used in the next step without further purification.

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 24241-18-7.

Reference:
Article; Huang, Boshi; Liang, Xin; Li, Cuicui; Chen, Wenmin; Liu, Tao; Li, Xiao; Sun, Yueyue; Fu, Lu; Liu, Huiqing; De Clercq, Erik; Pannecouque, Christophe; Zhan, Peng; Liu, Xinyong; European Journal of Medicinal Chemistry; vol. 93; (2015); p. 330 – 337;,
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. 6705-33-5, name is Pyrazin-2-ylmethanol, A new synthetic method of this compound is introduced below., 6705-33-5

Step 1: Intermediate 40-a [0220] To a solution of intermediate 29-g (4.62 g, 19.1 mmol) and pyrazin-2-ylmethanol (2.10 g, 19.1 mmol) in THF (38 mL) were sequentially added triphenylphosphine (7.50 g, 28.6 mmol) and DIAD (5.19 ml, 26.7 mmol) at room temperature and the reaction was then stirred at room temperature overnight. Volatiles were removed under reduced pressure. Purification by silica gel chromatography provided intermediate 40-a as a colorless oil.

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; Pharmascience, Inc.; Laurent, Alain; Rose, Yannick; Jaquith, James B.; US2015/191473; (2015); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

A common compound: 486460-20-2, name is 3-(Trifluoromethyl)-[1,2,4]triazolo[4,3-a]pyrazine, belongs to Pyrazines compound, it can change the direction of chemical reaction, and react with certain compounds to generate new functional products. A new synthetic method of this compound is introduced below. 486460-20-2

3-(Trifluoromethyl)-l,2,4-triazolo[4,3-a] pyrazine (540 mg, 2.87 mmol, from Step A)was hydrogenated under atmospheric hydrogen with 10% Pd/C (200 mg) as a catalyst in ethanol (10 mL)at ambient temperature for 18 h. Filtration through Celite followed by concentration gave a dark coloredoil. Dichloromethane was added to the above oil and the insoluble black precipitate was filtered off.Concentration of the filtrate gave the title compound as an oil.’H NMR (500 MHz, CDC13) 5 2.21 (br, 1H), 3.29 (t, 2H, J = 5.5 Hz), 4.09 (t, 2H, J = 5.5 Hz), 4.24 (s,2H); LC-MS 193 (M+l).

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, 486460-20-2, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; MERCK & CO., INC.; WO2006/23750; (2006); A2;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

5900-13-0, 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. 5900-13-0, name is 5-Bromo-3-methoxypyrazin-2-amine, This compound has unique chemical properties. The synthetic route is as follows.

3-Methoxy-5-vinylpyrazin-2-amine A mixture of 5-bromo-3-methoxypyrazin-2-amine (800 mg, 3.92 mmol, 1 eq.; Jiang, B. et al. Bioorg. Med. Chem (2001 ), 9, 1149-1 154.), trivinylboroxine pyri- dine-complex (944 mg, 3.92 mmol, 1.0 eq), tetrakis(triphenylphosphin)palladium(0) (45 mg, 0.04 mmol, 0.01 eq) and potassium carbonate (542 mg, 3.92 mmol, 1.0 eq) in 40 ml_ dimethoxyethane/water (3/1) was stirred at room temperature for 10 min and then heated to reflux temperature for 3 hours. The reaction mixture was hydrolysed with 100 ml_ of water and extracted with ethyl acetate. The resulting organic phase was washed with brine, dried with sodium sulphate and concentrated in vacuo. The crude mixture was purified via MPLC (column: Snap cartridge, eluent: hexane -> hexane/ethyl acetate 1/1) to deliver 495 mg (78%) of the title compound. UPLC-MS (Method 2): RT = 0.87 min; m/z = 152 (M+H) +.

If you are interested in these compounds, you can also browse my other articles.Thank you for taking the time to read this article. I hope you enjoyed it.

Reference:
Patent; BAYER INTELLECTUAL PROPERTY GMBH; BAYER PHARMA AKTIENGESELLSCHAFT; BAeRFACKER, Lars; SCOTT, William; HAeGEBARTH, Andrea; INCE, Stuart; REHWINKEL, Hartmut; POLITZ, Oliver; NEUHAUS, Roland; BOeMER, Ulf; WO2013/104610; (2013); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

A common compound: 19745-07-4, name is 2,5-Dichloropyrazine, belongs to Pyrazines compound, it can change the direction of chemical reaction, and react with certain compounds to generate new functional products. A new synthetic method of this compound is introduced below. 19745-07-4

Step G: To a solution of (3S)-l-(3,3-dimethylpiperidin-4-yl)-3-(2-fluoro-4-(methylsulfonyl)phenylamino)pyrrolidin-2-one (0.010 g, 0.026 mmol) in DMF (1 mL) was added 2,5-dichloropyrazine (0.0078 g, 0.052 mmol) and N-ethyl-N-isopropylpropan-2-amine (0.018 mL, 0.10 mmol) and the reaction was stirred for 3 hours at 100 ¡ãC. The reaction was cooled, poured into brine and extracted into EtOAc. The organic layer was washed with water and brine, dried over MgS04, filtered and concentrated under vacuum. Reverse phase HPLC purification of the crude material gave (3S)-l-(l-(5-chloropyrazin-2-yl)-3,3- dimethylpiperidin-4-yl)-3-(2-fluoro-4-(methylsulfonyl)phenylamino)pyrrolidin-2-one (0.0023 g, 0.0046 mmol, 18percent yield) as a white solid. XH NMR (CDC13, 400 MHz) delta 1.02 (s, 3H), 1.03 (s, 3H), 1.81 – 1.91 (m 1H), 2.12 – 2.21 (m, 1H), 2.71 – 2.81 (m, 2H), 2.95 – 3.05 (m, 2H), 3.03 (m, 3H), 3.52 (dd, 2H), 3.97 (d, 1H), 4.15 – 4.23 (m, 2H), 4.47 – 4.51 (m, 1H), 5.12 (bs, 1H), 6.80 (t, 1H), 7.55 (d, 1H), 7.61 (d, 1H), 7.90 (s, 1H), 8.05 (s, 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, 19745-07-4, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; ARRAY BIOPHARMA INC.; AICHER, Thomas Daniel; BENCSIK, Josef Roland; BOYD, Steven Armen; CONDROSKI, Kevin Ronald; FELL, Jay Bradford; FISCHER, John P.; HINKLIN, Ronald Jay; PRATT, Scott Alan; SINGH, Ajay; TURNER, Timothy M.; WO2011/146335; (2011); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem