Pyrazines

Electric Literature of 5049-61-6, 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. 5049-61-6, name is Pyrazin-2-amine, This compound has unique chemical properties. The synthetic route is as follows.

Step 1 imidazo[1,2-c]pyrazine Pyrazin-2-amine 4a (5 g, 52 mmol) was dissolved in a 40% 2-chloroacetaldehyde solution (15 mL, 78 mmol), followed by addition of sodium bicarbonate (6.60 g, 78 mmol). After stirring for 48 hours at 100 C., the reaction mixture was cooled to room temperature, added with 100 mL of a saturated potassium carbonate solution, and extracted with dichloromethane (100 mL*3). The organic phase was combined, dried over anhydrous sodium sulfate and filtered. The filtrate was concentrated under reduced pressure to obtain imidazo[1,2-a]pyrazine 4b (3 g, yield 50.0%) as a brown solid. MS m/z (ESI): 120.1 [M+1]

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

Reference:
Patent; JIANGSU HANSOH PHARMACEUTICAL CO., LTD.; Tang, Peng Cho; Li, Xin; Li, Xiangqin; Chen, Yang; Wang, Bin; Zhu, Zhe; US2013/131068; (2013); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 25911-65-3, A common heterocyclic compound, 25911-65-3, name is 3-Aminopyrazine-2-carbonitrile, molecular formula is C5H4N4, 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.

General procedure: Substrate (1.0 mmol), [HDBN+][TFE-] (6.0 mmol) were loaded in a 10 mL glass reaction tube equipped with a magnetic stirrer. The air in the reactor was replaced by CO2. Then, the reactor was stirred at the desired temperature for 3-96 h under CO2 using a balloon. After the reaction, the reaction liquid was cooled to room temperature and quenched by saturated ammonium chloride solution. Then the mixture was filtered to afford the crude product, which was purified by chromatography (silica gel, methanol/dichloromethane=1/20) to give the desired compound. The purified product was characterized by NMR and HR-MS. 1H NMR and 13C NMR studies were carried out with a JEOL NMR 400 (400 MHz, 100 MHz) spectrometer with DMSO-d6 as the solvent. Mass spectra were recorded with an AMD40223(Interambulacra) spectrometer.

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; Li, Chun; Lu, Xunhua; Yang, Yuanyong; Yang, Shenggang; Zhang, Lin; Tetrahedron Letters; vol. 59; 25; (2018); p. 2463 – 2466;,
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. 4774-14-5, name is 2,6-Dichloropyrazine, This compound has unique chemical properties. The synthetic route is as follows., Application In Synthesis of 2,6-Dichloropyrazine

To a solution of diisopropylamine (13.0 niL, 92.6 mmol, 2.3 eq.) in anhydrousTHF (300 rnL) at -78C under N2 was added dropwise a solution of 1.6 M nBuLi in hexanes (57.9 rnL, 92.6 mmol, 2.3 eq.). After 1 hour a solution of 2,6-dichloropyrazine in anhydrous THF (6.0 g, 40.3 mmol) was added dropwise over 30 minutes. After stirring at -78C for 1 hour, the reaction mixture was poured onto crushed dry ice (solid carbon dioxide), and the reaction mixture was stirred at ambient temperature for 16 hours. The mixture was then diluted with water (100 mL) and washed with ethyl acetate (3 x 100 mL). The aqueous layer was cooled to 00C, acidified with 2N HCl until pH ~ 2, and extracted with ethyl acetate (3 x 100 mL). The combined organic extracts were dried (Na2SO4), filtered and evaporated in vacuo. The resultant crude was purified by column chromatography (Si-PPC, gradient 0% to 50%, methanol in dichloromethane) to give the desired product as a beige solid (3.16 g, 40.6 %). 1H NMR (CDCl3, 400MHz) delta ppm 8.60 (s, IH).

According to the analysis of related databases, 4774-14-5, the application of this compound in the production field has become more and more popular.

Reference:
Patent; GENENTECH, INC.; WO2009/85983; (2009); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

These common heterocyclic compound, 25710-18-3, name is 2,3-Dichloropyrido[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. Quality Control of 2,3-Dichloropyrido[2,3-b]pyrazine

[0445] Example 14 [0446] Synthesis of 3 -(4-(3 -chlorobenzyl)piperazin- 1 -yl)-N-phenylpyrido [2,3 -b]pyrazin-2- amine, 2,2,2-trifluoroacetic acid salt [0447] To a solution of 2,3-dichloropyrido[2,3-b]pyrazine (20 mg, 0.100 mmol) in dioxane (0.3 mL) was added aniline (9.78 mg, 0.105 mmol) and -ethyl-N-isopropylpropan-2-amine (38.8 mg, 0.30 mmol). The reaction mixture was heated at 150 °C overnight, then l-(3- chlorobenzyl)piperazine (31.6 mg, 0.150 mmol) was added. The resulting solution was heated at 150 °C overnight. HPLC purification afforded the title compound as a yellow solid. MS (ESI, pos. ion) m/z: 431.2 (M+l)

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

Reference:
Patent; ENVOY THERAPEUTICS, INC.; HITCHCOCK, Stephen; MONENSCHEIN, Holger; REICHARD, Holly; SUN, Huikai; KIKUCHI, Shota; MACKLIN, Todd; HOPKINS, Maria; WO2014/28479; (2014); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 6164-79-0, 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. 6164-79-0, name is Methyl 2-pyrazinecarboxylate, This compound has unique chemical properties. The synthetic route is as follows.

Example 261; 5-Phenyl-2-(3-pyrazin-2-yl-ureido)-thiophene-3-carboxylic acid (S)-azepan-3-ylamide pyrazine-2-carbohydrazide. ; To a stirred solution of methyl pyrazine-2-carboxylate (11.1 g, 80 mmol) in 140 mL of EtOH was added hydrazine hydrate (15.6 mL, 320 mmol). The resultant solution was heated to reflux for 2h. The solvent was removed under reduced pressure and dried under high vacuum to yield the title amide (11.1 g, 100%) as a white solid. The product was used in subsequent steps without purification.’H NMR (d6-DMSO 8 10.1, br s, 1H; 8 9.12, d, 1H ; 8 8. 83, d, 1H ; 8 8.70, dd, 1H; 8 4.64, br s, 2H), LC/MS (APCI, ES, M+H=139).

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

Reference:
Patent; ASTRAZENECA AB; ASTRAZENECA UK LIMITED; WO2005/66163; (2005); A2;,
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. 939412-86-9, name is (3-Chloropyrazin-2-yl)methanamine hydrochloride, This compound has unique chemical properties. The synthetic route is as follows., SDS of cas: 939412-86-9

To a solution of 5- (methoxycarbonyl) tricyclo [3.2.2.02, 4] nonane-1-carboxylic acid (440 mg, 1.962 mmol) in anhydrous CH2Cl2 (8 ml) was added Et3N (0.820 ml, 5.89 mmol) , (3-chloropyrazin-2-yl) methanamine, HCl (424 mg, 2.354 mmol) and HATU (895 mg, 2.354 mmol) . The reaction mixture was stirred at 15 for 12 hours. The reaction was quenched by the addtion of water (10 mL) , then it was extracted with DCM (20 mL x 3) , the combined organic layers were washed with brine (20 mL) , dried over sodium sulfate, filtered and concentrated to afford the crude product , which was purified on silica gel column chromatograph (PE /EA 100 50 ) to give methyl 5- ( ( (3-chloropyrazin-2-yl) methyl) carbamoyl) tricyclo [3.2.2.02, 4] nonane-1-carboxylate. 1H NMR (400MHz, CDCl3) delta 8.47 (d, J2.5 Hz, 1H) , 8.33 (s, 1H) , 4.70 (d, J4.8 Hz, 2H) , 3.72 (s, 3H) , 2.08 -1.83 (m, 4H) , 1.68 -1.59 (m, 4H) , 1.42 (br. s., 1H) , 1.25 (d, J7.3 Hz, 1H) , 0.84 -0.78 (m, 1H) , 0.68 -0.61 (m, 1H) ppm.

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 939412-86-9.

Reference:
Patent; MERCK SHARP & DOHME CORP.; LIU, Jian; KOZLOWSKI, Joseph A.; ANDRESEN, Brain M.; BOGA, Sobhana Babu; GAO, Xiaolei; GUIADEEN, Deodialsingh; CAI, Jiaqiang; LIU, Shilan; WANG, Dahai; WU, Hao; YANG, Chundao; (111 pag.)WO2016/106624; (2016); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Some common heterocyclic compound, 1379338-74-5, name is 5,7-Dichloropyrido[3,4-b]pyrazine, molecular formula is C7H3Cl2N3, 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. name: 5,7-Dichloropyrido[3,4-b]pyrazine

Intermediate 29: 1,1-Dimethylethyl 3-{[(7-chloropyrido[3,4-b]pyrazin-5-yl)oxy]methyl}-4,4-difluoro-1-piperidinecarboxylate 1,1-Dimethylethyl 4,4-difluoro-3-(hydroxymethyl)-1-piperidinecarboxylate (207 mg, 0.825 mmol) was dissolved in dry N,N-dimethylformamide (DMF) (5 ml) and sodium hydride (45.0 mg, 1.125 mmol) was added under nitrogen at room temperature. After 60 min, 5,7-dichloropyrido[3,4-b]pyrazine (150 mg, 0.750 mmol) was added and the reaction was stirred at room temperature under nitrogen for 2 h. The reaction was quenched by the addition of sat. ammonium chloride solution and extracted with ethyl acetate. The aqueous layer was extracted further with ethyl acetate. The combined organics were washed with water, dried using a hydrophobic frit and evaporated in vacuo to give an orange oil (369 mg). The residue was loaded in dichloromethane and purified on silica (50 g) column using a 0-100% ethyl acetate/cyclohexane gradient. Appropriate fractions were combined and evaporated to give the title compound as an orange oil (163 mg). LCMS (Method B): Rt=1.25 min, MH+=415

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 1379338-74-5, its application will become more common.

Reference:
Patent; GLAXO GROUP LIMITED; Atkinson, Francis Louis; Atkinson, Stephen John; Barker, Michael David; Douault, Clement; Garton, Neil Stuart; Liddle, John; Patel, Vipulkumar Kantibhai; Preston, Alexander G.; Shipley, Tracy Jane; Wilson, David Matthew; Watson, Robert J.; US2014/5188; (2014); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 312736-49-5, name is 3,5-Dichloropyrazine-2-carboxylic acid, 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 312736-49-5, Safety of 3,5-Dichloropyrazine-2-carboxylic acid

To a solution of 3,5-dichloro-pyrazine-2-carboxylic acid (0.50 g, 2.60 mmol) in dimethylformamide (8 ml) is added potassium carbonate (0.54 g, 3.90 mmol) at RT followed by the addition of methyl iodide (0.8 ml,13.0 mmol). The resulting mixture is stirred at RT for 1 h. After completion of the reaction, the mixture is diluted with water (15 ml) and extracted with EtOAc (3 x 20 ml). The combined organic layers are washed with water (20 ml), brine (20 ml), dried over anhydrous sodium sulfate and evaporated in vacuo to get 3,5-dichloro-pyrazine-2-carboxylic acid methyl ester (0.45 g, 2.18 mmol, 84%), which is used in the next step without further purification.

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, 3,5-Dichloropyrazine-2-carboxylic acid, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; GRUeNENTHAL GMBH; LUCAS, Simon; KUHNERT, Sven; BAHRENBERG, Gregor; SCHROeDER, Wolfgang; WO2014/82739; (2014); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 24241-18-7,Some common heterocyclic compound, 24241-18-7, name is 2-Amino-3,5-dibromopyrazine, molecular formula is C4H3Br2N3, 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.

Intermediate Example 1 -1 : Preparation of 6,8-dibromo-imidazo[ 1 ,2-a]pyrazineTo a stirred suspension of 2-amino-3,5-dibrompyrazine (427 g, 1688mmol) in water (6.4 L) / THF (482 mL), at rt was added bromacetaldehyde-diethylacetal (998 g, 5065 mmol) in one portion. After stirring under reflux for 4 h, the clear orange solution was stirred for an additional 15 h at rt. The suspension was filtered, and the remaining solid was washed with MeOH (2 L) and dried in vaccuo at 60 C to yield 6,8-dibromo-imidazo[1 ,2-a]pyrazine as an off-white solid (500 g, 107% with residual MeOH): 1 H-NMR (300 MHz, d6-DMSO): delta =9.02 (s, 1 H), 8.23 (d, 1 H), 7.89 (d, 1 H) ppm. UPLC-MS: RT = 0.80 min; m/z 277.9 [MH+]; required MW = 276.9.

The synthetic route of 24241-18-7 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; BAYER PHARMA AKTIENGESELLSCHAFT; KOPPITZ, Marcus; KLAR, Ulrich; JAUTELAT, Rolf; KOSEMUND, Dirk; BOHLMANN, Rolf; BADER, Benjamin; LIENAU, Philip; SIEMEISTER, Gerhard; WO2012/80236; (2012); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 32587-10-3, name is 3-Aminopyrazine-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 32587-10-3, SDS of cas: 32587-10-3

12 g of 3-aminopyrazine-2-carboxamide was added to 150 ml of acetic acid, 19 g of bromoform was slowly added, and the mixture was heated under reflux and stirred for 3 hours. The mixture was concentrated, water and ethyl acetate were added for extraction, concentrated, and the residue was applied to a silica gel column. 10 g of 3-amino-6-bromopyrazine-2-carboxamide was isolated.

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-Aminopyrazine-2-carboxamide, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; Changsha Shencheng Biological Technology Co., Ltd.; Bu Gonggaofamingren; (5 pag.)CN107513041; (2017); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem