Month: November 2020

5049-61-6, A common compound: 5049-61-6, name is Pyrazin-2-amine, belongs to Pyrazines compound, it can change the direction of chemical reaction, and react with certain compounds to generate new functional products. A new synthetic method of this compound is introduced below.

Example 1 1-(5-{[3-(Cyclopropylmethyl)-2,3,4,5-tetrahydro-1 H-3-benzazepin- 7 -yl]oxy}-2- pyrazinyl)-2-pyrrolidinone (E1) Step 1: 5-Chloro-2-pyrazinamine; Aminopyrazine (10g, 10.5mmole) was dissolved in dry dimethylformamide (60ml) and was treated with N-chlorosuccinimide (15.36g, 11.5mmole) under argon at 0C. The mixture was stirred for 30 minutes and then allowed to warm to room temperature. The mixture was poured onto water and extracted with diethyl ether (x 5). The diethyl ether layers were combined and evaporated in vacuo. The resulting residue was purified by column chromatography (1: 9 ethyl acetate: pentane) to afford the title compound (1.40g). ?H NMR (CDCI3) 8.02 (1H, s), 7.76 (1H, s), 4.61 (2H, s).

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, Pyrazin-2-amine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; GLAXO GROUP LIMITED; WO2005/97778; (2005); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

A common heterocyclic compound, 274-79-3, name is Imidazo[1,2-a]pyrazine, 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. 274-79-3.

The title compound was prepared from imidazo[1,2-a]pyrazine (500 mg, 4.20 mmol, from Step A) and platinum oxide (250 mg) in methanol (50 mL), using a procedure analogous to that described in Example 1, Step B. Concentration gave the title compound (512 mg) as a viscous oil. 1H NMR (500 MHz, CD3OD) delta 3.37 (t, 1H, J=5.5 Hz), 4.18 (t, 2H, J=5.6 Hz), 4.88 (s, 1H), 7.27 (d, J=1.6 Hz, 1H), 7.33 (d, 1H)

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

Reference:
Patent; Merck Sharp & Dohme Corp.; Edmondson, Scott D.; Fisher, Michael H.; Kim, Dooseop; Maccoss, Malcolm; Parmee, Emma R.; Weber, Ann E.; Xu, Jinyou; US2015/359793; (2015); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

5049-61-6, Adding a certain compound to certain chemical reactions, such as: 5049-61-6, name is Pyrazin-2-amine, 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 5049-61-6.

To a stirred solution of aminopyrazine (8.21 g, 86.4 mmol) in anhydrous methylene chloride (215 mL) cooled to 00C was added N-bromosuccinimide (32.3 g, 181 mmol) in portions over a six hour period, during which time the temperature of the reaction was kept below 00C. The resulting mixture was stored at 4C overnight, after which it was stirred vigorously and quenched with H2O (100 mL). The organic layer was separated, after which it was washed with saturated aqueous NuaHCC>3, washed with brine, dried over MgSO4, filtered, and evaporated in vacuo to yield a residue that was triturated with 20% EtOAc in hexanes to yield the title compound (10.3 g, 47%) as a yellow/brown powder. 1H NMR (CDCl3, 300MHz) delta 8.02 (s, IH), 5.05 (bs, 2H); HPLC retention time: 1.99 minutes; MS ESI (m/z): 252.0/254.0/256.2 (M+ 1)+, calc. 251.

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, Pyrazin-2-amine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; UNIVERSITY OF ROCHESTER; GELBARD, Harris, A.; DEWHURST, Stephen; GOODFELLOW, Val, S.; WIEMANN, Torsten; WO2010/68483; (2010); A2;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

98-97-5, A common heterocyclic compound, 98-97-5, name is Pyrazine-2-carboxylic acid, molecular formula is C5H4N2O2, 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 pyrazine-2-carboxylic acid (Aldrich, 12.41 g, 0.1 mol) in MeOH (Aldrich, anhydrous, 100 mL) was stirred with H2SO4 (Aldrich, concentrated, 2 mL) at reflux for 6 hours. The reaction mixture was then concentrated and treated with saturated aqueous Na2CO3 solution (20 mL) till pH=8-9. The mixture was extracted with EtOAc (3*100 mL), and the combined extracts were washed with brine (2*20 mL) and dried over MgSO4. The drying agent was removed by filtration. The organic solution was concentrated and dried to give the title compound 1H NMR (300 MHz, CDCl3) delta 4.06 (s, 3H), 8.73 (dd, J=2.4, 1.6 Hz, 1H), 8.79 (d, J=2.4 Hz, 1H), 9.33 (d, J=1.6 Hz, 1H) ppm. MS (DCI/NH3) m/z 139 (M+H)+.

The synthetic route of 98-97-5 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; ABBOTT LABORATORIES; US2009/306096; (2009); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

274-79-3, name is Imidazo[1,2-a]pyrazine, 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. 274-79-3

Step 2: 5,6,7,8-Tetrahydroimidazo[1,2-a]pyrazine Imidazo[1,2-a]pyrazine (250 mg, 2.1 mmol) and palladium on carbon (10%) (55.8 mg, 0.53 mmol) were placed in a pressure resistant bottle and suspended under nitrogen in 0.5M HCl/EtOH. The mixture was stirred under at 45 psi H2 for 16 hrs. LC/MS showed completion. The next day, the reaction mixture was passed through celite cake. The filtrate was concentrated under reduced pressure to afford a tan solid. This was used directly without further purification. MS: [M+H]=124.2; Calc’d for C6H9N3: 123.2.

Statistics shows that 274-79-3 is playing an increasingly important role. we look forward to future research findings about Imidazo[1,2-a]pyrazine.

Reference:
Patent; CEE, Victor J.; DEAK, Holly L.; DU, Bingfan; GEUNS-MEYER, Stephanie D.; HUA, Zihao; MARTIN, Matthew W.; MARX, Isaac; NGUYEN, Hanh Nho; OLIVIERI, Philip R.; PANTER FABER, Kathleen; ROMERO, Karina; SCHENKEL, Laurie; WHITE, Ryan; US2014/336182; (2014); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

23611-75-8, A common compound: 23611-75-8, name is Methyl 6-chloropyrazine-2-carboxylate, belongs to Pyrazines compound, it can change the direction of chemical reaction, and react with certain compounds to generate new functional products. A new synthetic method of this compound is introduced below.

Example 66Methy[ 6- ({4-[(3,4-dif[uoropheny[)carbamoy[]-3-methy[- 1 ,2-thiazo[-5-y[lamino)-pyrazine-2-carboxy[ate A mixture of 5-amino-N-(3,4-dif[uoropheny[)-3-methy[-1 ,2-thiazo[e-4-carboxamide [Intermediate 3] (150 mg, 0.56 mmo[, 1.0 eq), methy[ 6-ch[oropyrazine-2- carboxy[ate [CAS RN: 23611-75-8] (120 mg, 0.56 mmo[, 1.0 eq) and cesiumcarbonate (417 mg, 1.28 mmo[, 2.3 eq) in 5.4 mL dioxane/DMF (7/1) was p[aced ina microwave via[ and f[ushed with argon. Then, pa[[adium(II) acetate (13 mg,0.06 mmo[, 0.1 eq) and Xantphos (32 mg, 0.06 mmo[, 0.1 eq) were added. The via[was capped and the reaction mixture was stirred at an environmenta[ temperatureof 110 C overnight. On coo[ing, the vo[ati[e components were removed in vacuo.The crude materia[ was disso[ved in a sma[[ amount DM50 and fi[tered. Purificationwas conducted via preparative HPLC (method A) to give 10 mg (4 % yie[d of theory) of the tit[e compound.UPLC-MS (Method 1): R = 1.20 mm; MS (ESIneg) m/z = 404 [M-H].1H-NMR (400 MHz, DMSO-d6): oe [ppm] = 3.98 (s, 3H), 7.38-7.53 (m, 2H), 7.95 (m,1H), 8.73 (s, 1H), 8.84 (s, 1H), 10.48 (s, 1H), 11.22 (s br, 1H), 1xCH3 not assigned.

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 6-chloropyrazine-2-carboxylate, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; BAYER PHARMA AKTIENGESELLSCHAFT; BAeRFACKER, Lars; PRECHTL, Stefan; SIEMEISTER, Gerhard; WENGNER, Antje Margret; ACKERSTAFF, Jens; NOWAK-REPPEL, Katrin; BADER, Benjamin; LIENAU, Philip; STOeCKIGT, Detlef; WO2014/118186; (2014); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

63744-22-9, Adding a certain compound to certain chemical reactions, such as: 63744-22-9, name is 6,8-Dibromoimidazo[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 63744-22-9.

General procedure: 6,8-dibromoimidazo[1,2-a]pyrazine (6, 1.86 g, 6.72 mmol) was added to asolution of 3a-3c, 5a-5e (5.6 mmol), DIPEA (1.4 mL, 8.4 mmol) inisopropanol (60 mL), stirred at 85 C for 8 h, and then the solvent wasevaporated to dryness. The crude product was purified by columnchromatography to obtain the desired intermediates 7a, 11a-11 g.

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, 6,8-Dibromoimidazo[1,2-a]pyrazine, other downstream synthetic routes, hurry up and to see.

Reference:
Article; Fan, Yan; Huang, Zhi; Li, Yao; Qin, Zhongxiang; Wang, Cheng; Wang, Tianqi; Wang, Xin; Xiang, Rong; Yang, Shengyong; Bioorganic Chemistry; vol. 95; (2020);,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

38557-72-1, A common compound: 38557-72-1, name is 2-Chloro-3,5-dimethylpyrazine, belongs to Pyrazines compound, it can change the direction of chemical reaction, and react with certain compounds to generate new functional products. A new synthetic method of this compound is introduced below.

1.42 g of 2-chloro-3,5-dimethylpyrazine which was obtained as the intermediate obtained in the Step 1 of the above synthesis example 2, 1.40 g of 4-fluorophenyl boronic acid, 1.06 g of sodium carbonate, 0.046 g of bis(triphenylphosphine)palladium(II)dichloride (abbreviation : Pd(PPh3)2Cl2), 15 mL of water, and 15 mL of acetonitrile were put in an eggplant flask equipped with a reflux pipe, and the inside thereof was substituted by argon. This reaction container was subjected to irradiation with microwave (2.45 GHz, 100W) for 10 minutes to be heated. Then, water was added to this solution, and extraction using dichloromethane was conducted and an organic layer was extracted. The organic layer obtained was washed with water and dried with magnesium sulfate. After the drying, the solution was filtrated. A solvent of this solution was distilled off. Then the residue obtained by the distillation was purified by silica gel column chromatography which uses dichloromethane as a developing solvent; thereby obtaining an objective pyrazine derivative HdmFppr (white powder, yield of 77 %). A synthetic scheme of Step 1 is shown by the following (a-3).

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-Chloro-3,5-dimethylpyrazine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; SEMICONDUCTOR ENERGY LABORATORY CO., LTD.; WO2008/149828; (2008); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

123-32-0, These common heterocyclic compound, 123-32-0, name is 2,5-Dimethylpyrazine, 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.

Preparation of 3,6-dimethyl-2- (4-methylphenyl) benzoyl pyrazine, comprising the steps of: (1) Take 0.2 mmol 2,5-dimethyl pyrazine, methyl benzoyl formate 0.4mmol, 0.02 mmol silver phosphate, potassium persulfate 0.4mmol 5mL reaction tube was placed in dichloromethane was added 1.4mL , 0.6 mL of distilled water was added, and the mixture was placed in an oil bath at 40 heated, reaction 24h, cooled to room temperature to obtain a reaction solution;(2) The step (1) the resulting reaction mixture was directly concentrated to give a concentrate, the concentrate with ethyl acetate / petroleum ether = 1/2 (v / v) as the developing solvent, separation by thin layer chromatography to give 39mg target The product yield was 87%.

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 123-32-0.

Reference:
Patent; Henan Agricultural University; Wu Zhiyong; Zhao Mingqin; Li Yuan; (10 pag.)CN108101856; (2018); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding some certain compound to certain chemical reactions, such as: 5049-61-6, name is Pyrazin-2-amine, 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 5049-61-6. 5049-61-6

C1: According to the standard of adding 1 g of 2-cyanopyrazine to 20 ml of solvent, 100 ml of a sodium hypochlorite solution and 100 ml of a mixed solution of sodium hydroxide and potassium hydroxide are sequentially added to 10 g of 2-cyanopyrazine.The pH of the mixed solution of sodium hydroxide and potassium hydroxide is 8,Then stirring at 40 C for 2 hours, followed by hydrolysis, rearrangement to obtain 2-aminopyrazine; C2: the 2-aminopyrazine obtained in the step C1 is added to the bromine to carry out a bromination reaction for 0.5 hour to obtain 2-amino-3,5-dibromopyrazine; C3 The 2-amino-3,5-dibromopyrazine obtained in the step C2 is subjected to a substitution reaction with morpholine at 40 C for 0.5 hour in a molar ratio of 1:1 to obtain 2-amino-5-bromo-3- Morpholinylpyrazine solution; C4: 2-amino-5-bromo-3-morpholinylpyrazine was dissolved and distilled to remove an organic solvent, followed by washing with water for 2 hours to obtain crude 2-amino-5-bromo-3-morpholinylpyrazine; C5: The crude 2-amino-5-bromo-3-morpholinylpyrazine was repeatedly subjected to rectification three times to obtain a finished product.

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 Pyrazin-2-amine.

Reference:
Patent; Zaozhuang Jiu Xing Biological Technology Co., Ltd.; Sun Yan; (5 pag.)CN108570011; (2018); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem