Pyrazines

33332-29-5, Name is 2-Amino-5-chloropyrazine, 33332-29-5, belongs to pyrazines compound, is considered to be a conventional heterocyclic compound, which is widely used in drug synthesis. The chemical synthesis route is as follows.

Step A: S,S-Dimethyl-N-(5-chloropyrazin-2-yl)sulfilimine (5) Compound 5 is prepared from 2-amino-5-chloropyrazine as described above for 2 in Example 1A to afford pure 5 as a smelly, tan solid, m.p. 119-120.

Statistics shows that 2-Amino-5-chloropyrazine is playing an increasingly important role. we look forward to future research findings about 33332-29-5.

Reference:
Patent; Merck & Co., Inc.; US4609659; (1986); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 54608-52-5, 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 54608-52-5 as follows.

Ethyl 1-benzyl-2,4-dioxopiperidine-3-carboxylate (58.5 mg, 0.21 mmol) in EtOH (2 mL) was added to a biotage microwave vial under nitrogen containing 2-hydrazinopyrazine (38.5 mg, 0.35 mmol) at RT. To this stirred reaction mixture was added AcOH (0.024 mL, 0.42 mmol) and then stirred at RT for 18 hours in a sealed microwave vial. The reaction was heated to 140 C for 10 hours in the microwave reactor and cooled to RT. The reaction mixture was evaporated in the Genevac and then redissolved in 2 ml DMSO, filtered and the crude product was purified by flash RP chromatography (35g Puriflash, 15mu, HC column), using decreasingly polar mixtures of water (containing 1% NH4OH) and MeCN as eluents. Fractions containing the desired compound were evaporated to dryness to afford 5-benzyl-2-(pyrazin-2-yl)-1,2,6,7-tetrahydro-3H-pyrazolo[4,3-c]pyridine-3,4(5H)-dione (14.6 mg, 19.2 %) as a white solid.

According to the analysis of related databases, 54608-52-5, the application of this compound in the production field has become more and more popular.

Reference:
Article; Fairley, Gary; Greenwood, Ryan; McMillan, Caroline Anne; Tetrahedron Letters; vol. 59; 39; (2018); p. 3574 – 3578;,
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. 6863-74-7, name is 6-Chloropyrazine-2-carbonitrile, This compound has unique chemical properties. The synthetic route is as follows., Recommanded Product: 6863-74-7

Reference Example 104 2-Cyano-6-methylthiopyrazine A mixture of 2-chloro-6-cyanopyrazine (1.40 g, 10.0 mmol), sodium thiomethoxide (0.78 g, 11.0 mmol) and THF (100 ml) was refluxed for 2 hrs.. The reaction mixture was combined with ethyl acetate and water.. The organic layer was washed with saturated brine and dried over magnesium sulfate.. The solvent was evaporated to give the titled compound (1.25 g, 83 %) as pale yellow crystals.1H-NMR (CDCl3) delta: 2.61 (3H, s), 8.49 (1H, s), 8.60 (1H, s). IR(KBr): 2241, 1670, 1521, 1390, 1190, 1167, 1138, 1108, 887, 734 cm-1.

According to the analysis of related databases, 6863-74-7, the application of this compound in the production field has become more and more popular.

Reference:
Patent; Takeda Chemical Industries, Ltd.; EP1424336; (2004); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 76537-18-3, A common heterocyclic compound, 76537-18-3, name is 3-Bromo-5-chloropyrazin-2-amine, molecular formula is C4H3BrClN3, 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.

3-Bromo-5-chloropyrazin-2-amine (200 mg, 0.96 mmol),Triethylamine (290 mg, 2.88 mmol), cuprous iodide(5mg, 0.33mmol)And bis(triphenylphosphine)palladium dichloride (13 mg, 0.02 mmol) was dissolved in tetrahydrofuran (5 mL).The reaction solution was stirred at room temperature.Then trimethylethynyl silicon (0.15 mL, 1.06 mmol)Slowly adding dropwise to the above reaction solution,After completion of the dropwise addition, the resulting reaction solution was heated to 55 C to continue the reaction for 1 hour.After the reaction system is cooled to room temperature,The reaction solution was diluted with ethyl acetate (50 mL).Filter and concentrate the filtrate under reduced pressure.The residue obtained was purified by silica gel column chromatography (PE/EA (v/v) = 30/1).The title compound was obtained as a pale yellow solid ( 208 g, 96%).

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; Guangdong Dongyangguang Pharmaceutical Co., Ltd.; Ren Qingyun; Tang Changhua; Yin Junjun; Yi Kai; Lei Yibo; Wang Yejun; Zhang Yingjun; Nie Biao; Xu Juan; Yan Huan; Chen Jianping; (90 pag.)CN108727369; (2018); 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. 32111-21-0, name is 2-Iodopyrazine, A new synthetic method of this compound is introduced below., COA of Formula: C4H3IN2

To a solution of 3-nitrophenol (0.151 g, 0.733 mmol) in DMSO (5 mL) was added NaH (35 mg of a 60% dispersion, 0.88 mmol) at 0 C under Ar atmosphere. After stirring for 30 min, 2-iodopyrazine (0.133 mg, 0.953 mmol) was added and mixture heated to 85 C for 4h. To the mixture was added satd. NH4Cl solution (25 mL) and the product extracted with EtOAc (2×25 mL). The combined organic extracts were washed with brine, dried (Na2SO4) and concentrated to yield a crude residue which was purified by column chromatography to afford (97 mg, 61% yield) 2-(3-nitrophenoxy)pyrazine as a white solid.

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; DECIPHERA PHARMACEUTICALS, LLC; WO2006/71940; (2006); A2;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 33332-28-4,Some common heterocyclic compound, 33332-28-4, name is 2-Amino-6-chloropyrazine, molecular formula is C4H4ClN3, 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.

[0504] Compound 481A was prepared by an analogous method as that of 473B, except using compound 2-chloro-6-aminopyrazine in place of compound 2-bromo-6-aminopyridine.

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

Reference:
Patent; Das, Jagabandhu; Padmanabha, Ramesh; Chen, Ping; Norris, Derek J.; Doweyko, Arthur M.P.; Barrish, Joel C.; Wityak, John; Lombardo, Louis J.; Lee, Francis Y.F.; US2004/54186; (2004); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 89123-58-0, The chemical industry reduces the impact on the environment during synthesis 89123-58-0, name is 5-Bromopyrazine-2,3-diamine, I believe this compound will play a more active role in future production and life.

Oxalyl chloride (3ml) was added to a solution of 5-({5-chloro-2-[(2-methylpropyl)oxy]- phenyl}methyl)-2-furancarboxylic acid (3.09g, lOmmol) and one drop of DMF in dichloromethane (30ml) and left at room temperature for one hour. The resulting solution was evaporated to dryness, azeotroped with toluene and the residue dissolved in dichloromethane (15ml) and added dropwise to a stirred solution of 2,3-diamino-5- bromopyrazine (2.08g, 11mmol) and 4-dimethyaminopyridine (100mg, 0.82mmol) in pyridine (20ml) and stirred for one hour. The solution was evaporated and the residue dissolved in ether/water. The organic phase was dried with magnesium sulphate, evaporated and chromatographed on silica gel eluting with ethyl acetate/hexane (15:85) to give 3.35g of white solid which was dissolved in acetic acid (40ml) and stirred and refluxed for 5 days. The resulting solution was evaporated, dissolved in ethyl acetate and washed with 2M sodium hydroxide solution. The organic phase was dried with magnesium sulphate, evaporated and purified by flash chromatography on silica eluting with ethyl acetate/hexane (1 :3) to give a pale yellow solid. A sample was dissolved in methanol/dichloromethane and hydrogen chloride in ether (1ml) was added. The solvent was evaporated and the residue triturated with ether and filtered off to give the title compound as a solid. LC/MS: Rt=3.67, [MH]+ 463.11 , 464.16.

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, 5-Bromopyrazine-2,3-diamine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; GLAXO GROUP LIMITED; WO2006/114272; (2006); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 5049-61-6, These common heterocyclic compound, 5049-61-6, name is Pyrazin-2-amine, 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.

To a solution of 2-aminopyrazine (i) (2 g, 21.02 mmol) in dry DCM (10 ml) was added NBS (3.78 g, 21.23 mmol) portion-wise under cold condition and the resulting mixture was allowed to stir at RT for 6h. 5 ml of water was added and the layers were separated. Aqueous layer was extracted with DCM (10 ml X 2). Combined organic layers were washed with Brine solution (5 ml), dried over anhydrous Na2S04 and concentrated under vacuum. Crude material was purified by column chromatography over silica gel 230-400 mesh by using 18% of ethyl acetate in petroleum ether as an eluent to afford compound (ii) (1.98 g, 54.42%) as white solid.

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

Reference:
Patent; UNIVERSITY OF CAPE TOWN; MMV MEDICINES FOR MALARIA VENTURE; YOUNIS, Yassir; CHIBALE, Kelly; WITTY, Michael, John; WATERSON, David; WO2013/121387; (2013); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 486424-37-7,Some common heterocyclic compound, 486424-37-7, name is 3-Amino-6-bromopyrazine-2-carboxylic acid, molecular formula is C5H4BrN3O2, 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.

CDI (2.23 g, 13.8 mmol) was added to a suspension of commercial 3-amino-6- bromopyrazine-2-carboxylic acid (2.00 g, 9.17 mmol) in DMF (20 ml). The reaction was stirred at RT for 16 h. The reaction mixture was cooled (0 C) then diluted with water (20 ml). The solid was collected by filtration then washed with the minimum volume of water and cooled (0 C) MeCN then dried under vacuum to afford the product as a yellow solid (2.23 g, 86%). 1H NMR (250 MHz, DMSO-cfe) delta 8.55 (s, 2H), 7.96 – 7.82 (m, 3H), 7.15 – 7.07 (dm, 1 H). LC/MS (System A, MeOH quench): m/z (ESI+) = 232 [Methyl ester M(79Br)H+], 234 [Methyl ester M(81Br)H+]), Rt = 0.87 min, UV purity = 95%.

The synthetic route of 486424-37-7 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; ENTERPRISE THERAPEUTICS LIMITED; MCCARTHY, Clive; HARGRAVE, Jonathan David; HAY, Duncan Alexander; SCHOFIELD, Thomas Beauregard; WENT, Naomi; (111 pag.)WO2017/221008; (2017); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 88625-24-5, 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. 88625-24-5 name is 5-Chloropyrazine-2-carbaldehyde, 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.

2) N,N-dimethylformamide (10 mL) was added to 5-chloropyrazine-2-carbaldehyde (500 mg), methyl 2,2-dimethyl-3-{[4-methyl-5-(4,4,5,5-tetramethyl-l,3,2-dioxaborolan- 2-yl)pyridin-2-yl]oxy}propanoate (1410 mg) and 2N aqueous sodium carbonate solution (5.26 mL), and after replacing the atmosphere with nitrogen, palladium chloride (dppf) methylene chloride complex (143 mg) was added to the mixture and the resulting mixture was stirred at 65C for 2 hours. To the reaction mixture were added ethyl acetate and water, and the liquids were separated. After filtration with Celite, the organic layer was separated, washed with water and then with a saturated brine, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The obtained residue was purified by silica gel column chromatography (n-hexane: ethyl acetate=100:0 to 70:30) to obtain methyl 3-{[5-(5-formylpyrazin-2-yl)-4-methylpyridin- 2-yl]oxy}-2,2-dimethylpropanoate (855 mg). MS (m/z): 330 [M+H]+

At the same time, in my other blogs, there are other synthetic methods of this type of compound, 5-Chloropyrazine-2-carbaldehyde, and friends who are interested can also refer to it.

Reference:
Patent; MITSUBISHI TANABE PHARMA CORPORATION; SAKURAI, Osamu; SARUTA, Kunio; HAYASHI, Norimitsu; GOI, Takashi; MOROKUMA, Kenji; TSUJISHIMA, Hidekazu; SAWAMOTO, Hiroaki; SHITAMA, Hiroaki; IMASHIRO, Ritsuo; WO2012/81736; (2012); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem