Month: September 2021

Application of 21279-62-9,Some common heterocyclic compound, 21279-62-9, name is 3-Chloropyrazine-2-carboxamide, molecular formula is C5H4ClN3O, 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: Compounds 1-6 were prepared according to conventional organic synthesis methods. 3-Chloropyrazine-2-carboxamide (1.27 mmol) was dissolved in THF (20 mL) in a round bottom flask and after that treated with two equivalents of the corresponding benzylamine and an equimolar amount of triethylamine. The reaction was conducted with continuous stirring and heating (70 C) under reflux in an oil bath for 15 h. Compounds 7-15 were synthesised using a microwave reactor with a focused field. 3-Chloropyrazine-2-carboxamide (1.27 mmol) was put into a thick-walled tube together with the corresponding benzylamine (2.54 mmol), pyridine (1.27 mmol), methanol (approx. 5 mL) and a magnetic stir bar and then sealed with a special cap. The reaction parameters were set according to the previously published paper as follows-140 C, 30 min, 200 W [29]. Reaction progress was checked by TLC (hexane:ethyl acetate-1:1). Regardless of the synthesis method used,all reaction mixtures were adsorbed on silica and subjected to preparative flash chromatography (hexane and ethyl acetate, gradient elution, detection wavelengths 260 nm and 280 nm). Products were recrystallized from ethanol or ethanol and water if necessary. All final substances were chemically characterized (1H-NMR, 13C-NMR, IR, melting point and elemental analysis).

The synthetic route of 21279-62-9 has been constantly updated, and we look forward to future research findings.

Reference:
Article; Jandourek, Ondrej; Tauchman, Marek; Paterova, Pavla; Konecna, Klara; Navratilova, Lucie; Kubicek, Vladimir; Holas, Ondrej; Zitko, Jan; Dolezal, Martin; Molecules; vol. 22; 2; (2017);,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 63286-28-2,Some common heterocyclic compound, 63286-28-2, name is 2-Chloro-3-hydrazinylpyrazine, molecular formula is C4H5ClN4, 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.

-Chloro-3-hydrazinylpyrazine (440 g, 3.0 mol) was suspended in acetic acid (500 mL) and cooled to lOoC. A solution of sodium nitrite (220 g, 3.2 mol) in water (200 mL) at 10 C was added. The resulting mixture was stirred at 10 C for 1 h, during which time a crystalline solid precipitated. The precipitate was collected by filtration, washed with ethanol (200 mL) and dried to afford the desired product as a red solid (350 g, 73% yield).

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

Reference:
Patent; KALYPSYS, INC.; CHEN, Pingyun; CARINO, Stephen, A., R.; COUCH, Ricky, W.; KINDER, Daniel, S.; NORTON, Beth, A.; WO2013/39785; (2013); 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. 16298-03-6, name is Methyl 2-aminopyrazine-3-carboxylate, This compound has unique chemical properties. The synthetic route is as follows., SDS of cas: 16298-03-6

Hydrazine hydrate (34 mL, 1.1 mol) was added portionwise to a stirred suspension of methyl 3-aminopyrazine-2-carboxylate 37 (21.3 g, 139 mmol) in ethanol (65 mL) at room temperature. The resulting slurry was stirred at 60 °C for 2 h, cooled to room temperature, and filtered. The solid was washed with cold ethanol (2 x 25 mL) and dried to a constant weight to afford 3-aminopyrazine-2-carbohydrazide (20.75 g, 97percent) as a beige solid. TBTU (5.77 g, 18.0 mmol) was added portionwise over 15 min to a stirred suspension of DIPEA (8.5 mL, 49 mmol), 1-methylcyclopropanecarboxylic acid (1.63 g, 16.3 mmol) and 3-aminopyrazine-2-carbohydrazide (2.50 g, 16.3 mmol) in acetonitrile (40 mL). The mixture was stirred at 80 °C for 20 min, and then cooled to 0 °C. DIPEA (8.5 mL, 49 mmol) followed by 4-methylbenzene-1-sulfonylchloride (9.34 g, 49 mmol) were added over a period of 15 min. The reaction mixture was brought to reflux and allowed to stir at room temperature for 14 h. The mixture was concentrated, and the residue was diluted with DCM, washed with water and brine, dried over magnesium sulfate and concentrated. The crude product was purified by flash chromatography on silica gel eluting with 0 to 40percent ethyl acetate in dichloromethane. After evaporation of the solvent, the resulting solid was triturated with diethyl ether, filtered, washed with the minimum of diethyl ether and dried to afford 3-(5-(1-methylcyclopropyl)-1,3,4-oxadiazol-2-yl)pyrazin-2-amine (2.12 g, 60percent). NBS (1.87 g, 10.5 mmol) was added portionwise to a solution of 3-(5-(1-methylcyclopropyl)-1,3,4-oxadiazol-2-yl)pyrazin-2-amine (2.08 g, 9.6 mmol) in THF (30 mL). The reaction mixture was stirred at room temperature for 16 h and concentrated. The residue was dissolved in dichloromethane (150 mL), washed with water (2 x 40 mL), brine, dried over magnesium sulfate and concentrated. After evaporation of the solvents, the crude product was purified by flash chromatography on silica gel eluting with 0 to 10percent ethyl acetate in dichloromethane. The solvent was evaporated to dryness to afford 5-bromo-3-(5-(1-methylcyclopropyl)-1,3,4-oxadiazol-2-yl)pyrazin-2-amine (2.50 g, 88percent) as a yellow solid. Bis(triphenylphosphine)palladium(II) chloride (59 mg, 0.08 mmol) was added in one portion to a stirred solution of 5-bromo-3-(5-(1-methylcyclopropyl)-1,3,4-oxadiazol-2-yl)pyrazin-2-amine (500 mg, 1.69 mmol) and hexamethyldistannane (0.49 mL, 2.4 mmol) dissolved in dioxane (8 mL) under argon. The resulting suspension was stirred at 80 °C for 1 h. The mixture was evaporated. The crude product was purified by flash chromatography on silica gel eluting with 10 to 30percent ethyl acetate in dichloromethane. The solvent was evaporated to dryness to afford 3-(5-(1-methylcyclopropyl)-1,3,4-oxadiazol-2-yl)-5-(trimethylstannyl)pyrazin-2-amine 38a (314 mg, 49percent) as a yellow crystalline solid.

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 16298-03-6.

Reference:
Article; Barlaam, Bernard; Cosulich, Sabina; Delouvrie, Benedicte; Ellston, Rebecca; Fitzek, Martina; Germain, Herve; Green, Stephen; Hancox, Urs; Harris, Craig S.; Hudson, Kevin; Lambert-Van Der Brempt, Christine; Lebraud, Honorine; Magnien, Francoise; Lamorlette, Maryannick; Le Griffon, Antoine; Morgentin, Remy; Ouvry, Gilles; Page, Ken; Pasquet, Georges; Polanska, Urszula; Ruston, Linette; Saleh, Twana; Vautier, Michel; Ward, Lara; Bioorganic and Medicinal Chemistry Letters; vol. 25; 22; (2015); p. 5155 – 5162;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 1379338-74-5,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.

Intermediate 33: 1,1-Dimethylethyl-2-{[(7-chloropyrido[3,4-b]pyrazin-5-yl)amino]methyl}-4-morpholinecarboxylate 1,1-Dimethylethyl-2-(aminomethyl)-4-morpholinecarboxylate (60 mg, 0.28 mmol) was dissolved in N-methyl-2-pyrrolidinone (NMP) (1 mL) and to this was added DIPEA (0.07 mL, 0.38 mmol) and 5,7-dichloropyrido[3,4-b]pyrazine (50 mg, 0.25 mmol). This was heated at 130 C. for 30 min. The reaction mixtures were partitioned between ethyl acetate (50 ml) and water (50 mL) and the organic layer washed with water (50 mL), dried over a hydrophobic frit and concentrated in vacuo to yield an orange gum. It was dissolved in DCM and passed through silica (10 g) eluting with a 10-40% ethyl acetate in cyclohexane gradient. Appropriate fractions were combined and concentrated in vacuo to yield the title compound as a yellow solid, 91 mg. LCMS (Method B): Rt=1.17 min, MH+ 380

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 5,7-Dichloropyrido[3,4-b]pyrazine, 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

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. 642459-03-8, name is 6-Chloro-N-phenylpyrazin-2-amine belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below. Application In Synthesis of 6-Chloro-N-phenylpyrazin-2-amine

tert-Buty 5-methyl-3-{[6-(phenylamino)pyrazin-2-yl]amino}pyrazole- carboxylate. 6-Chloro-N-phenylpyrazin-2-amine (84 mg, 0.4 mmol), tert-butyl 3-amino-5- methyl-lH-pyrazole-1-carboxylate (98 mg, 0.5 mmol), palladium acetate (10 mg, 0.04 mmol), 4,5-bis(diphenylphosphino)-9,9-dimethylxanthene (55 mg, 0.1 mmol), and potassium carbonate (560 mg, 4.0 mmol) were suspended in anhydrous dioxane (3 mL). The resulting mixture was degassed with nitrogen for 5 minutes and stirred at 90C for one hour. The reaction was then partitioned between ethyl acetate and water. The aqueous layer was extracted with ethyl acetate (3 x 20 mL), and the organic layers were combined and dried over magnesium sulfate. After filtration, the solvent was removed in vacuo. The residue was purified by silica gel chromatography (15-75% ethyl acetate in hexanes) to give the title compound as an off-white solid (68 mg, 0.19 mmol, 46% yield); 1H NMR (DMSO-^6) delta 9.45 (s, IH), 9.33 (s, IH), 7.81 (s, IH), 7.71 (s, IH), 7.52 (d, J= 8.4 Hz, 2H), 7.32 (t, J= 8.4 Hz, 2H), 7.01 (t, J= 7.6 Hz, IH), 6.53 (s, IH), 2.13 (s, 3H), 1.57 (s, 9H); MS (ESI) MS (ESI) m/z 367.3 [M+l]+.

The synthetic route of 642459-03-8 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; SIGNAL PHARMACEUTICALS, LLC; WO2009/89042; (2009); 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. 19847-12-2, name is Pyrazinecarbonitrile, A new synthetic method of this compound is introduced below., SDS of cas: 19847-12-2

In a 250 mL round-bottomed flask, pyrazine-2-carbonitrile (10 g, 95.1 mmol), pyridine (2.26 g, 2.33 ml, 28.5 mmol), and 2-mercaptopropionic acid (10.1 g, 95.1 mmol) were combined to give a light yellow solution. The reaction mixture was heated to 100 C. and stirred for 2 h. Upon cooling, the thick yellow mixture was diluted with 100 mL ethanol and stirred for 30 min. The slurry was then filtered, and washed with diethyl ether (2*100 mL) to give 5-methyl-2-pyrazin-2-yl-thiazol-4-ol (17.86 g, 97.1%) as yellow solid which was used directly without further purification. Trifluoro-methanesulfonic acid 5-methyl-2-pyrazin-2-yl-thiazol-4-yl ester:

The synthetic route of 19847-12-2 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Alam, Muzaffar; Du Bois, Daisy Joe; Hawley, Ronald Charles; Kennedy-Smith, Joshua; Minatti, Ana Elena; Palmer, Wylie Solang; Silva, Tania; Wilhelm, Robert Stephen; US2011/71150; (2011); A1;,
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 41110-33-2 as follows. category: Pyrazines

A solution of lithium aluminium hydride (164.0 mL, 0.164 mol, 1.0 M in THF, 0.5 equiv.) was added to a suspension of methyl 5-methylpyrazine-2-carboxylate (50 g, 0.328 mol, 1.0 equiv.) in anhydrous THF (750 mL) at -78 C. (The internal temperature was kept below -72 C during the addition of lithium aluminium hydride). Upon completion of addition, the reaction mixture was left, to stir at -78 C for a further 20 min and was then quenched with glacial AcOH (50.0 mL) at the same temperature. The resulting mixture was warmed to RT and the volatiles were removed by evaporation under pressure. The residue was dissolved in 1.5 N HCl (500 mL) and extracted with DCM (2 x 2 L). The extracts were combined, washed with saturated aqueous sodium hydrogen carbonate solution (2 x 500 mL), (Note: no product observed in HCl or aqueous sodium hydrogen carbonate solution) dried over anhydrous Na2SO4, and concentrated in vacuo, to yield the initial product as a brown oil. The residue was purified by column chromatography (silica gel 60-120 mesh) eluting with a gradient of 10% EtOAc in petroleum ether to provide the title compound as a pale yellow liquid (21.3 g, 53 %). TLC Info: (9.0/1.0 Petroleum ether/EtOAc). 1H NMR (400 MHz, CDCl3) delta 10.14 (s, 1H), 9.07 (d, J = 1.5 Hz, 1H), 8.63 (d, J = 1.4 Hz, 1H), and 2.70 (s, 3H). LCMS (ESI positive ion) m/z: 123 (M+H)+.

According to the analysis of related databases, 41110-33-2, the application of this compound in the production field has become more and more popular.

Reference:
Patent; AMGEN INC.; CHEN, Ning; CHEN, Yinhong; DEBENEDETTO, Mikkel V.; DRANSFIELD, Paul John; HARVEY, James S.; HEATH, Julie Anne; HOUZE, Jonathan; KHAKOO, Aarif Yusuf; LAI, Su-Jen; MA, Zhihua; NISHIMURA, Nobuko; PATTAROPONG, Vatee; SWAMINATH, Gayathri; YEH, Wen-Chen; KREIMAN, Charles; (308 pag.)WO2018/93579; (2018); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 6966-01-4, 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. 6966-01-4, name is Methyl 3-amino-6-bromopyrazine-2-carboxylate belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below.

A mixture of palladium (II) acetate (145 mg, 0.65 mmol) and 1,1′-bis(diphenylphosphino)-ferrocene (493 mg, 0.86 mmol) in DMF (70 ml) was stirred at 50 C. for 15 minutes and cooled to r.t. The mixture was evacuated and vented with argon. 3-Amino-6-bromopyrazine-2-carboxylic acid methyl ester (5.0 g, 21.5 mmol), furan-3-yl-boronic acid (2.79 g, 23.7 mmol) and triethylamine (4.51 ml, 32.3 mmol) were added and the reaction mixture was stirred at 90 C. for 16 h. The solvent was evaporated and the product was obtained after purification by silica gel chromatography using a heptane /ethyl acetate gradient as yellow solid (2.92 g, 61.8%). MS: M=220.2 (M+H)+

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, Methyl 3-amino-6-bromopyrazine-2-carboxylate, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; Bleicher, Konrad; Flohr, Alexander; Groebke Zbinden, Katrin; Gruber, Felix; Koerner, Matthias; Kuhn, Bernd; Peters, Jens-Uwe; Sarmiento, Rosa Maria Rodriguez; US2011/306589; (2011); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 117103-53-4, 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 117103-53-4 as follows.

Example 73 2 (R)- (3-Chloro-4-methanesulfonyl-phenyl)-3-cyclopentyl-N- [5- (2-hydroxy- ETHYLAMINO)-PYRAZIN-2-YL]-PROPIONAMIDE [000339] A mixture of 2-bromo-5-nitropyrazine (500 mg, 2.45 mmol) and ethanolamine (225 mg, 3.67 mmol) in methanol (15 mL) was stirred at 25C for 5 h. After such time, the reaction was concentrated in vacuo. Biotage chromatography (FLASH 40S, Silica, 20/80 hexanes/ethyl acetate to 97/3 ethyl acetate/methanol) afforded 2- (5-NITRO-PYRAZIN-2-YLAMINO)-ETHANOL (375 mg, 83%) as a yellow solid: mp 157.5- 159. 8C ; EI-HRMS m/e calcd for C6H8N403 (M+) 184.0596, found 184.0603.

According to the analysis of related databases, 117103-53-4, the application of this compound in the production field has become more and more popular.

Reference:
Patent; F. HOFFMANN-LA ROCHE AG; WO2004/52869; (2004); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 4858-85-9, name is 2,3-Dichloropyrazine, 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 4858-85-9, Recommanded Product: 4858-85-9

A. Preparation of the intermediate compoundsA1. Preparation of intermediate compound 3 a) Preparation of intermediate compound 12,3-Dichloropyrazine (10 g, 62.12 mmol) and 1-(phenylmethyl)-4-piperidin- amine (13.73 ml_, 67.12 mmol) were dissolved in DMF (60 ml). Then Na2CO3 (10.09 g, 114.10 mmoi) was added. The reaction was stirred at 130 0C for 16 hours. The solid was filtered off, washed with AcOEt and the solvent was evaporated till dryness. The product was dissolved in AcOEt, washed with H2O and brine, dried with MgSO4 and evaporated under vacuum. The product was used without any further purification yielding 15 g of the desired intermediate compound 1 (74 %).

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

Reference:
Patent; JANSSEN PHARMACEUTICA N.V.; WO2007/71639; (2007); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem