Pyrazines

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. 768-05-8, name is Pyrazinoic acid hydrazide, A new synthetic method of this compound is introduced below., Formula: C5H6N4O

A solution of (+-)-1-(2-chloro-3-(trifluoromethyl)benzyl)-6-cyclopropyl-3-methoxy-5,6-dihydropyrazin-2(1H)-one (216 mg, 0.58 mmol) and pyrazine-2-carbohydrazide (88 mg, 0.63 mmol) in 1-butanol (5.8 mL) was heated at 130 C. for 16 h. After cooling to rt, the solvent was removed in vacuo. Purification by chromatography (SiO2; hexanes-100% EtOAc) afforded the desired product as a white solid (116 mg, 45%). MS (ESI): mass calcd. for C20H16ClF3N6O, 448.1; m/z found, 449.1 [M+H]+. 1H NMR (400 MHz, CDCl3) delta 9.69-9.58 (m, 1H), 8.70 (d, J=2.6 Hz, 1H), 8.64 (dd, J=2.5, 1.5 Hz, 1H), 7.75-7.62 (m, 2H), 7.38 (t, J=7.8 Hz, 1H), 5.49 (d, J=15.9 Hz, 1H), 5.27-5.16 (m, 1H), 4.78 (dd, J=15.6, 1.7 Hz, 1H), 4.68 (ddd, J=13.9, 4.5, 2.4 Hz, 1H), 3.16 (ddd, J=9.9, 4.5, 3.3 Hz, 1H), 1.06-0.96 (m, 1H), 0.80-0.72 (m, 1H), 0.67-0.43 (m, 2H), 0.28-0.21 (m, 1H).

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; Janssen Pharmaceutica NV; Ameriks, Michael K.; Rech, Jason C.; Savall, Brad M.; US2014/275096; (2014); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 457099-42-2, A common heterocyclic compound, 457099-42-2, name is 5-Ethynylpyrazin-2-amine, molecular formula is C6H5N3, 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: 2-Amino-5-ethylpyrazine. To a stirred solution of 5-ethynyl-2-aminopyrazine (18 mg; 0.151 mmol), in ethyl acetate (500 muL) was added triethylamine (63 muL; 0.45 mmol) and Pd(OH)2 (0.01 mmol; 20% wt on carbon). The reaction was placed under a hydrogen atmosphere at 45 psi and shook for 6 hours. The reaction was filtered and concentrated under reduced pressure to yield an off white solid (84% yield).

The synthetic route of 457099-42-2 has been constantly updated, and we look forward to future research findings.

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

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. 33332-28-4, name is 2-Amino-6-chloropyrazine, This compound has unique chemical properties. The synthetic route is as follows., Computed Properties of C4H4ClN3

(d) N-(6-Chloro-pyrazin-2-yl)-4-hydroxy-2-methyl-2H-1,2-benzothiazine-3-carboxamide-1,1-dioxide This compound was prepared from 4-hydroxy-2-methyl-N-cyclohexyl-2H-1,2-benzothiazine-3-carboxamide-1,1-dioxide, 2-amino-6-chloro-pyrazine and p-toluenesulfonic acid analogous to Example 14. Yield: 68percent of theory. Melting point: 278¡ã-279¡ã C. (decomposition). C14 H11 ClN4 O4 S (366.79). Calc.: C–45.84percent; H–3.03percent; Cl–9.67percent; N–15.28percent; S–8.74percent. Found: C–45.68percent; H–3.04percent; Cl–9.69percent; N–15.12percent; S–8.60percent.

According to the analysis of related databases, 33332-28-4, the application of this compound in the production field has become more and more popular.

Reference:
Patent; Dr. Karl Thomae Gesellschaft mit beschrankter Haftung; US4533664; (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. 16298-03-6, name is Methyl 2-aminopyrazine-3-carboxylate, A new synthetic method of this compound is introduced below., Computed Properties of C6H7N3O2

Bromine (3.91 g, 24.46 mmol) was added dropwise to a stirred mixture of 3- aminopyrazine-2-carboxylic acid methyl ester (1.27 g, 8.29 mmol) and hydrobromic acid (4.70 mL, 41.5 mmol) at 00C. A solution of sodium nitrite (1.44 g, 20.9 mmol) in water (6 mL) was then added dropwise. The reaction mixture was stirred for 15 min, brought to pH 8 with NaHCO3 (saturated, aqueous), and extracted with ethyl acetate (80 mL) and chloroform (50 mL). The combined organics were dried over MgSO4 and concentrated in vacuoto give 1.13 g (63%) of an orange oil which solidified on standing.

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; BAYER PHARMACEUTICALS CORPORATION; WO2006/91506; (2006); A2;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

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 59303-10-5 as follows. Computed Properties of C5H5ClN2

The rac- I -((2S,3R,4R)-4-amino-2-ethyl-6-fluoro-3-methyl-3,4-dihyd roquinolin- I (2H)-yl)ethanone (for a preparation see Intermedaite 40, 100 mg, 0.400 mmol), 2-chloro-5-methylpyrazine (77mg, 0.599mmo1), Pd2(dba)3 (54.9 mg, 0.060 mmol), sodium tert-butoxide (115 mg, 1.199 mmol) andDavePhos (15.72 mg, 0.040 mmol) were suspended I ,4-dioxane (10 mL) and allowed to stir at 100C for 18 h. The reaction was allowed to cool to rt and were filtered through celite and concentratedto a gum. This gum was purified using a MDAP (Formic) to give a solid, this solid was eluted througha NH2 SPE (5 g) with MeOH, the eluent was concentrated and dried to give the product (50 mg,0.146 mmol, 36.6%) as an off-white solid. LCMS (2 mm Formic): Rt = 0.89 mi [MH] = 343.

According to the analysis of related databases, 59303-10-5, the application of this compound in the production field has become more and more popular.

Reference:
Patent; GLAXOSMITHKLINE INTELLECTUAL PROPERTY (NO.2) LIMITED; AMANS, Dominique; ATKINSON, Stephen John; HARRISON, Lee Andrew; HIRST, David Jonathan; LAW, Robert Peter; LINDON, Matthew; PRESTON, Alexander; SEAL, Jonathan Thomas; WELLAWAY, Christopher Roland; WO2014/140076; (2014); 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. 622392-04-5, name is 2-Bromo-5-iodopyrazine, A new synthetic method of this compound is introduced below., Application In Synthesis of 2-Bromo-5-iodopyrazine

Intermediate 31 (200 mg, 0.602 mmol), 2-bromo-5-iodopyrazine (172 mg, 0.602 mmol), 2M aqueous sodium carbonate solution (0.903 mL, 1.807 mmol) and anhydrous DMSO (2 mL) were charged to a sealed tube. The mixture was degassed by bubbling30 with nitrogen for 5 minutes before the addition of tetrakis(triphenylphosphine)palladium(0) (35 mg, 0.03 mmol). The mixture was sealed under nitrogen, then stirred at100C for 1 h. The reaction mixture was partitioned between water (25 mL) and EtOAc(50 mL), then the organic phase was washed with saturated aqueous NaHCO3 solution(10 mL) and brine (10 mL), dried over sodium sulfate and concentrated under vacuum. The residue was purified by FCC, eluting with a gradient of 17-100% EtOAc in heptane, to afford the title compound (160 mg, 42%) as an off white solid. oH (500 MHz, CDC13) 8.72-8.68 (m, 2H), 7.93 (s, 2H), 7.33-7.26 (m, 2H), 7.18 (d, J8.0 Hz, 1H), 7.13 (t, J7.55 Hz, 1H), 7.01 (t, J8.3 Hz, 1H), 6.82-6.52 (t, 1H), 4.36 (s, 2H), 2.61 (s, 3H).

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; UCB PHARMA S.A.; BENTLEY, Jonathan Mark; BROOKINGS, Daniel Christopher; BROWN, Julien Alistair; CAIN, Thomas Paul; CHOVATIA, Praful Tulshi; FOLEY, Anne Marie; GALLIMORE, Ellen Olivia; GLEAVE, Laura Jane; HEIFETZ, Alexander; HORSLEY, Helen Tracey; HUTCHINGS, Martin Clive; JACKSON, Victoria Elizabeth; JOHNSON, James Andrew; JOHNSTONE, Craig; KROEPLIEN, Boris; LECOMTE, Fabien Claude; LEIGH, Deborah; LOWE, Martin Alexander; MADDEN, James; PORTER, John Robert; QUINCEY, Joanna Rachel; REED, Laura Claire; REUBERSON, James Thomas; RICHARDSON, Anthony John; RICHARDSON, Sarah Emily; SELBY, Matthew Duncan; SHAW, Michael Alan; ZHU, Zhaoning; WO2014/9295; (2014); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 16298-03-6,Some common heterocyclic compound, 16298-03-6, name is Methyl 2-aminopyrazine-3-carboxylate, molecular formula is C6H7N3O2, 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 : Methyl S-amino–bromopyrazine-l-carboxylate[00210] A mixture of methyl 3-aminopyrazine-2-carboxylate (8.35 g, 54.53 mmol) and N- bromo-succinimide (9.705 g, 54.53 mmol) was stirred in MeCN (100 mL) at room temp overnight. The resultant precipitate was filtered, washed with MeCN and dried to give the desired product as a yellow solid (11.68 g, 92percent Yield) 1H NMR (400.0 MHz, DMSO) 3.85 (s, 3H), 7.55 (br s, 2H) and 8.42 (s, IH) ppm; MS (ES+) 233

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

Reference:
Patent; VERTEX PHARMACEUTICALS INCORPORATED; CHARRIER, Jean-damien; DURRANT, Steven; KAY, David; O’DONNELL, Michael; KNEGTEL, Ronald; MACCORMICK, Somhairle; PINDER, Joanne; VIRANI, Anisa; YOUNG, Stephen; BINCH, Hayley; CLEVELAND, Thomas; FANNING, Lev, T.d.; HURLEY, Dennis; JOSHI, Pramod; SHETH, Urvi; SILINA, Alina; WO2010/54398; (2010); 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. 873-40-5, name is 2,3,5-Trichloropyrazine, This compound has unique chemical properties. The synthetic route is as follows., Product Details of 873-40-5

28.5 g (152.65 mmol) of 2,3,5-trichloropyrazine, 23.8 g (152.65 mmol) of 2-chlorophenylboronic acid, 63.3 g (457.9 mmol) of K2CO3 and 800 ml / 200 ml of THF/H2O were added under nitrogen atmosphere and stirred. 5.3 g (4.58 mmol) of Pd (PPh3) 4 was added at 40 DEG C, and the mixture was stirred at 80 DEG C for 12 hours. After completion of the reaction, the reaction mixture was extracted with dichloromethane. The organic layer was dried over MgSO4 and filtered under reduced pressure. The filtered organic layer was distilled under reduced pressure, and 12 g (yield: 30%) of 2,5-dichloro-3- (2-chlorophenyl) pyrazine was obtained by column chromatography.

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 873-40-5.

Reference:
Patent; Doosan Co., Ltd; Kim Tae-hyeong; Bae Hyeong-chan; Son Hyo-seok; Baek Yeong-mi; Park Ho-cheol; (53 pag.)KR101920101; (2018); B1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

These common heterocyclic compound, 91476-80-1, name is 5,6,7,8-Tetrahydroimidazo[1,2-a]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 5,6,7,8-Tetrahydroimidazo[1,2-a]pyrazine

2-Fluoro-5-[(4-oxo-3H-phthalazin-1-yl)methyl]benzoic acid 1a (323 mg, 1.08 mmol) was dissolved in 5 mL of N, N-dimethylformamide, followed by addition of O-(1-benzotriazolyl)-N, N, N’, N’-tetramethyluronium hexafluorophosphate (614 mg, 1.63 mmol), 5,6,7,8-tetrahydroimidazo[1,2-a]pyrazine 4c (200 mg, 1.63 mmol) and N, N-diisopropylethylamine (0.4 mL, 2.16 mmol). After stirring for 12 hours, the reaction mixture was concentrated under reduced pressure and the resulting residue was purified by thin layer chromatography with elution system A to obtain 4-[[3-(6,8-dihydro-5H-imidazo[1,2-a]pyrazine-7-carbonyl)-4-fluoro-phenyl]methyl]-2H-phthalazin-1-one 4 (10 mg, yield 2.3%) as a white solid. MS m/z (ESI): 404.1 [M+1] 1H NMR (400 MHz, CDCl3): delta 10.07 (br. s, 1H), 8.53 (d, 1H), 7.96 (m, 1H), 7.83 (m, 3H), 7.51 (m, 1H), 7.30 (m, 2H), 6.01 (t, 1H), 4.73 (d, 2H), 4.35 (s, 2H), 1.60 (m, 2H), 1.34 (m, 2H)

The synthetic route of 5,6,7,8-Tetrahydroimidazo[1,2-a]pyrazine has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Jiangsu Hansoh Pharmaceutical Co., Ltd.; TANG, Pengcho; LI, Xin; LI, Xiangqin; CHEN, Yang; WANG, Bin; ZHU, Zhe; EP2604610; (2013); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 21943-12-4, name is 2-Amino-3-bromopyrazine, 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 21943-12-4, Recommanded Product: 21943-12-4

A suspension of 2-amino-3-bromopyrazine (2.5 g, 19.3 mmol) in DME (20 mL) was added 3-bromo-1, 1, 1-trifluoroacetone (13.7g, 72.Ommol) and 4A molecular sieves (1.0 g). The reaction mixture was then stined at 90 C for 4h and quenched by the addition of water (25mL).This mixture was extracted with ethyl acetate. The combined organic layers were washed with brine (10 mL), dried over anhydrous sodium sulphate and concentrated under reduced pressure to give 8-chloro-2-trifluoromethyl-imidazo [1,2-a] pyrazine (0.8g, 25%). ?H NMR (400 MHz, CDC13): oe 8.13- 8.10 (m, 2H), 7.84-7.82 (m, 1H); LC-MS: 268.3.0 [M+2Hj.

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-Amino-3-bromopyrazine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; AURIGENE DISCOVERY TECHNOLOGIES LIMITED; KOTRABASAIAH UJJINAMATADA, Ravi; PANDIT, Chetan; (152 pag.)WO2016/185342; (2016); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem