Pyrazines

These common heterocyclic compound, 486424-37-7, name is 3-Amino-6-bromopyrazine-2-carboxylic acid, 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. name: 3-Amino-6-bromopyrazine-2-carboxylic acid

Step 1. Synthesis of tert-butyl (l-(2-(3-amino-6-bromopyrazine-2-carboxamido) pyridin- 3 -y l)piperidin-4-yl)carbamate In a 100 mL round-bottom flask equipped with a magnetic stirrer, a solution of 3-amino- 6-bromopyrazine-2-carboxylic acid (1.044 g, 4.79 mmol), tert- butyl (l-(2-aminopyridin-3- yl)piperidin-4-yl)carbamate (1.4 g, 4.79 mmol), DIPEA (2.091 mL, 11.97 mmol) and HATU (2.185 g, 5.75 mmol) in DMF (15 mL) was stirred at 25 C for 15 hr. The reaction mixture was quenched with 30 mL water and extracted with EtOAc (3 X 20 mL). The ethyl acetate wash was dried over Na2S04 and concentrated. The crude product was purified by silica gel chromatography using ethyl acetate and heptane which gave 3-amino-N-(3-(4-aminopiperidin-l- yl)pyridin-2-yl)-6-bromopyrazine-2-carboxamide (1.76 g, 3.57 mmol) in 74 % yield. LC-MS (acidic method): : ret.time= 1.17 min, M+H = 492.3.

The synthetic route of 3-Amino-6-bromopyrazine-2-carboxylic acid has been constantly updated, and we look forward to future research findings.

Reference:
Patent; NOVARTIS AG; LUZZIO, Michael Joseph; PAPILLON, Julien; VISSER, Michael Scott; (213 pag.)WO2016/20864; (2016); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 33332-25-1, A common heterocyclic compound, 33332-25-1, name is Methyl 5-chloropyrazine-2-carboxylate, molecular formula is C6H5ClN2O2, 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.

863 mg of 5-chloropyrazine-2-carboxylic acid methyl ester was dissolved in 13 ml of N, N-dimethylformamide, 0.67 ml of 1-methylpiperazine and 5 ml of N, N-diisopropylethyl The mixture was heated to 80 C under argon, and the mixture was heated for 2 hours. After heating, the reaction solution was diluted with 65 ml of water and extracted with ethyl acetate. The organic phases were combined and washed with saturated aqueous sodium chloride solution five times, Dried over sodium, filtered and concentrated, and the residue was subjected to column chromatography (dichloromethane: methanol = 99: 1-97: 3, v / v) to give 1.024 g of a yellowish solid in 86.7% yield.

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

Reference:
Patent; Chinese Academy Of Sciences Shanghai Pharmaceutical Institute; Duan Wenhu; Geng Meiyu; Zhao Bin; Ding Jian; Ai Jing; Fan Jun; Peng Xia; Yan Wei; Chen Yi; (77 pag.)CN106146493; (2016); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 768-05-8,Some common heterocyclic compound, 768-05-8, name is Pyrazinoic acid hydrazide, molecular formula is C5H6N4O, 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: To a stirred solution of the acid hydrazide 5 (2mmol, 0.27g) in absolute ethanol (10ml), the appropriate heteroaromatic ketone or substituted pyrazolaldehyde (2mmol) was added in the presence of catalytic amount of glacial acetic acid (5 drops), the mixture was refluxed for 12-16h. The product obtained was filtered, washed with diethyl ether, dried and recrystallized from ethanol.

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

Reference:
Article; Hassan, Nayera W.; Saudi, Manal N.; Abdel-Ghany, Yasser S.; Ismail, Azza; Elzahhar, Perihan A.; Sriram, Dharmarajan; Nassra, Rasha; Abdel-Aziz, Marwa M.; El-Hawash, Soad A.; Bioorganic Chemistry; vol. 96; (2020);,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 5049-61-6, A common heterocyclic compound, 5049-61-6, name is Pyrazin-2-amine, molecular formula is C4H5N3, 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.

A solution of dichloromethane (200 mL) and pyridine (25.3 mL, 0.315 mol) was added to a three-necked flask containing 2-aminopyrazine (14.27 g, 0.15 mol) and stirred well. In the dark and while refluxing a solution of bromine (16.2 mL, 0.315 mol) in dichloromethane (100 mL) was slowly added dropwise to the three-necked flask. About 1 h later the addition finished and the mixture was refluxed at 40 C for 30 min more. After TLC monitoring indicated the reaction was complete, the reaction mixture was cooled to room temperature and distilled water (50 mL) was added and themixture was stirred vigorously for 10 min. Then the organic layer was collected and washed twice with distilled water. Silica gel (10 g) and activated carbon (1 g) were added to the organic layer and the mixture was decolorized under reflux for 30 min. After hot filtration, the filtrate was collected and vacuum distilled. The residue was refluxed with n-hexane (45 mL) for 2 h, filtered while hot again and the solid product was dried and weighed to give 18.15 g of a pale yellow solid (47.8% yield). 1H-NMR(DMSO-d6) delta 8.14 (s, 1H), 7.01 (s, 2H).

The synthetic route of 5049-61-6 has been constantly updated, and we look forward to future research findings.

Reference:
Article; Xu, Shan; Sun, Chengyu; Chen, Chen; Zheng, Pengwu; Zhou, Yong; Zhou, Hongying; Zhu, Wufu; Molecules; vol. 22; 2; (2017);,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 912773-21-8,Some common heterocyclic compound, 912773-21-8, name is 2-Bromo-5-chloropyrazine, molecular formula is C4H2BrClN2, 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.

A mixture of 2-bromo-5-chloro-pyrazine (2 g, 10.34 mmol), 3-fluoro-5-(4,4,5,5-tetramethyl-l,3,2-dioxaborolan-2-yl)-2-(2,2,2-trifluoro-l,l- dimethyl-ethoxy)pyridine (3.61 g, 10.34 mmol), CS2CO3 (6.74 g, 20.68 mmol) andPd(dppf)Cl2 (1.13 g, 1.55 mmol) in l,4-Dioxane (80 mL) and Water (8 mL) was stirred at 55 C under N2 for 5 hours. The mixture was cooled to room temperature and concentrated to give a residue. To the residue was added water (50 mL) and extracted with EtOAc (50 mL x 2). The combined organic phase was washed with water (50 mL), brine (50 mL x 2), dried over anhydrous Na2S04, filtered and concentrated to give the crude product. The crude product was purified by flash chromatography column on silica gel (EtOAc in PE = 0% to 5% to 10%) to give the product (2.3 g, 5.45 mmol) as a solid. ‘H NMR (400 MHz, CDCI3) dH= 8.77 (d, 1H), 8.64 (d, 1H), 8.53 (d, 1H), 8.05 (dd, 1H), 1.88 (s, 6H). LCMS R, = 0.96 min in 1.5 min chromatography, MS ESI calcd. for Ci3HnClF4N30 [M+H]+336.0, found 335.9.

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-chloropyrazine, its application will become more common.

Reference:
Patent; PRAXIS PRECISION MEDICINES, INC.; GRIFFIN, Andrew, Mark; MARRON, Brian, Edward; MARTINEZ BOTELLA, Gabriel; REDDY, Kiran; WITTMANN, Marion; (0 pag.)WO2019/232209; (2019); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 143591-61-1, 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. 143591-61-1, name is 3-Bromo-8-chloroimidazo[1,2-a]pyrazine belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below.

To a solution of 3-bromo-8-chloro-imidazo[l,2-a]pyrazine (4.0 g, 18.2 mmol) in DMF (16 ml.) MeSNa (1.52 g, 21.8 mmol) is added and stirred at 70 0C for 2h. After this time the solution is allowed to cool, poured into 16ml_ of water, stirred for 30 minutes and the solid obtained filtered off and washed with water (3 x 5OmL). The product, 3-Bromo-8-methylsulfanyl- imidazo[l,2-a]pyrazine was obtained as a beige solid (3.21 g, 72.3 %).

The synthetic route of 3-Bromo-8-chloroimidazo[1,2-a]pyrazine has been constantly updated, and we look forward to future research findings.

Reference:
Patent; BIOFOCUS DPI LIMITED; WO2009/24585; (2009); A2;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 54013-06-8, 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. 54013-06-8, name is Ethyl 5-aminopyrazine-2-carboxylate belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below.

Example 3 5-{[(6-Bromo-3-methyl-2-phenylquinolin-4-yl)carbonyl]amino}pyrazine-2-carboxylic acid (0773) (0774) 100 mg (0.26 mmol) of the compound from example 2A and 43 mg (0.26 mmol) of 377 ethyl 5-aminopyrazine-2-carboxylate were dissolved in 2 ml of 49 DMF. 72 mg (0.64 mmol) of 153 potassium tert-butoxide were added in portions to the solution. The reaction mixture was stirred at RT overnight, and then 1.3 ml (1.3 mmol) of 1 M 196 sodium hydroxide solution were added. After stirring at 80 C. for 1 h and cooling to RT, the mixture was adjusted to pH 1-2 with 1 M hydrochloric acid. The mixture was extracted with ethyl acetate, and the organic phase was removed and washed with saturated sodium chloride solution. After the organic phase had been dried over sodium sulfate and the solvent had been removed on a rotary evaporator, the residue was taken up in a little DMF and purified by means of preparative HPLC (method 6). After the solvent-water mixture had been removed, the residue was taken up in a little acetonitrile, water was added and then the mixture was lyophilized. Since solvent residues were still present, the lyophilizate was redissolved in 124 dichloromethane and 61 ethyl acetate, 43 water was added again and the mixture was lyophilized again. The resulting lyophilizate was redissolved once again in dichloromethane and 378 tert-butanol, water was added and the mixture was lyophilized again. The lyophilizate thus obtained was dried at 100 C. under high vacuum for a total 9 h. In this way, 39 mg (29% of theory, 90% purity) of the 379 title compound were obtained. (0775) 1H-NMR (600 MHz, DMSO-d6): delta [ppm]=13.54 (br. s, 1H), 12.03 (s, 1H), 9.71 (s, 1H), 9.01 (s, 1H), 8.10 (d, 1H), 8.04 (d, 1H), 7.93 (dd, 1H), 7.66-7.60 (m, 2H), 7.58-7.50 (m, 3H), 2.41 (s, 3H). (0776) LC/MS (Method 1, ESIpos): Rt=0.96 min, m/z=463/465 [M+H]+.

The synthetic route of Ethyl 5-aminopyrazine-2-carboxylate has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Bayer Pharma Aktiengesekkschaft; BECK, Hartmut; THALER, Tobias; KAST, Raimund; MEIBOM, Daniel; MEININGHAUS, Mark; TERJUNG, Carsten; DELBECK, Martina; LUSTIG, Klemens; MUENSTER, Uwe; OLENIK, Britta; (100 pag.)US2017/260140; (2017); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 143591-61-1, name is 3-Bromo-8-chloroimidazo[1,2-a]pyrazine, 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 143591-61-1, Formula: C6H3BrClN3

To a solution of compound 2 (example 1, step 2) (80 mg, 0,28 mmoi) in THE (5 mL) was added NaH (22 mg, 0.56 mmoi, 60 wt% in oil) at RI. The mixture was stirred at RT for 30 minutes, then the product from step 1 (81 rng, 0.35 mmoi) was added. The mixture was heated to 60C for 3 hours. After cooling to RT, the mixture was poured into water (5 mL) and extracted with EtOAc (5 niL x 3). The combined organic layer was washed with brine, driedover MgSO4, filtered and concentrated in vacuo. The residue was purified by Prep.?FIPLC to afford the title compound (70 mg) as a white solid. LRMS mz (M+H) 482.1, 484.1 found, 482.1,484.1

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, 3-Bromo-8-chloroimidazo[1,2-a]pyrazine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; MERCK SHARP & DOHME CORP.; LIVERTON, Nigel; KUDUK, Scott D.; BESHORE, Doug C.; MENG, Na; LUO, Yunfu; (127 pag.)WO2016/101119; (2016); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 110223-15-9, name is 2-Amino-3-benzyloxypyrazine, 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 110223-15-9, Computed Properties of C11H11N3O

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).

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

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

Synthetic Route of 6966-01-4,Some common heterocyclic compound, 6966-01-4, name is Methyl 3-amino-6-bromopyrazine-2-carboxylate, molecular formula is C6H6BrN3O2, 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.

To a solution of methyl 3-amino-6-bromopyrazine-2-carboxylate (100 mg, 0.43 mmol) in MeOH (5 mL) was added 2 mL of NaOH aqueous solution (5 N). After being stirred at 50C for 4 h, the mixture was cooled and acidified with 1 M HCl to a pH of 2. The precipitate was collected by filtration and washed with water to afford the product of 3-amino-6- bromopyrazine-2-carboxylic acid (90 mg, yield: 96%). XH-NMR (DMSO-ifc, 400 MHz) delta 8.38 (s, 1H), 7.51-7.56 (m, 2H). MS (M+H)+: 218 / 220.

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route Methyl 3-amino-6-bromopyrazine-2-carboxylate, its application will become more common.

Reference:
Patent; MERCK SHARP & DOHME CORP.; DAI, Xing; LIU, Hong; PALANI, Anandan; HE, Shuwen; NARGUND, Ravi; XIAO, Dong; ZORN, Nicolas; DANG, Qun; MCCOMAS, Casey, C.; PENG, Xuanjia; LI, Peng; SOLL, Richard; WO2014/209727; (2014); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem