Category: Pyrazines

Synthetic Route of 32974-92-8, These common heterocyclic compound, 32974-92-8, name is 1-(3-Ethylpyrazin-2-yl)ethanone, 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.

General procedure: Previous method was used for preparing Ligands (L1-L7). Ethanol(10 mL, 1 mM) solution of piperidylthiosemicarbazide was added to corresponding aldehyde or ketone (one mole equivalent) and 5 drops of acetic acid glacial, with stirred and refluxed for 4 h. The precipitate was filtered with filter paper and rinsed with Cold ethanol. A vacuum desiccator was applied to dry the precipitate.

Statistics shows that 1-(3-Ethylpyrazin-2-yl)ethanone is playing an increasingly important role. we look forward to future research findings about 32974-92-8.

Reference:
Article; Qi, Jinxu; Yao, Qian; Qian, Kun; Tian, Liang; Cheng, Zhen; Wang, Yihong; Journal of Inorganic Biochemistry; vol. 186; (2018); p. 42 – 50;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 123-32-0,Some common heterocyclic compound, 123-32-0, name is 2,5-Dimethylpyrazine, molecular formula is C6H8N2, 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.

2, 5-dimethylpyrazine (6 g, 55.6 mmol), carbon tetrachloride (50 mL) were added in a three-necked flask,After stirring, N-chlorosuccinimide (NCS) (7. 4 g, 55.6 mmol) and benzoyl peroxide(0. 05 g, 0.21 mmol),The reaction mixture was irradiated under incandescent light,Stir,Reflux reaction about 18h,TLC [V (ethyl acetate): V (petroleum ether) = 1: 2 as developing solvent] After the detection reaction is substantially complete,The reaction solution was cooled to 0 C,After standing for 1 hour,filter,The filter cake is washed with cold carbon tetrachloride,Combined filtrate and wash solution,Vacuum distillation of carbon tetrachloride,Get a light brown oil,Methylene chloride dissolved,After decolorization of activated carbon,Pale yellow oil,Without further direct reaction to the next step.

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 2,5-Dimethylpyrazine, its application will become more common.

Reference:
Patent; Anhui University of Chinese Medicine; Hefei Industrial Pharmaceutical Institute Co., Ltd.; Li, JiaMing; He, GuangWei; Hu, MinHua; Huang, WeiJun; Zhu, Xiaoyu; Wang, Jie; Ye, WenFeng; Zhang, EnLi; (10 pag.)CN103664804; (2016); B;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 32111-21-0, A common heterocyclic compound, 32111-21-0, name is 2-Iodopyrazine, molecular formula is C4H3IN2, 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.

Example 47; S-fS^-Chloro-phenyl^-oxo–^-pyrazin-?-yl-pheny?^.S-dihvdro-pyrazolorB^-dipyrimidin- 1 -yll-benzonitrile; [00175] A solution of 3-{5-(4-chloro-phenyl)-4-oxo-6-[4-(4 ,4,5,5-tetramethyl-[l ,3,2]- dioxaborolan-2-yl)-phenyl]-4,5-dihydro-pyrazolo[3,4-d]pyrimidin-l-yl}-benzonitrile (prepared as described in example 28, 3.6 g, 6.54 mmol) in N,N-dimethylformamide (70 mL) is degassed with argon for 0.5 h. Then 2-iodopyrazine (2.0 g, 9.82 mmol), cesium carbonate (4.2 g, 13.09 mmol), Pd(dppf)2Cl2 (0.53 g, 0.654 mmol) is added and the resulted mixture is degassed with argon for 0.5 h The reaction mixture is then heated at 100 0C for 1.5 h. The reaction mixture is cooled to rt and diluted with water and extracted with ethyl acetate (3 x). The combined organic layer is washed with brine, dried over Na2SO4, concentrated, and purified by column chromatography to afford 3-[5-(4-chloro-phenyl)-4-oxo-6-(4-pyrazin-2- yl-phenyl)-4,5-dihydro-pyrazolo[3,4-d]pyrimidin-l-yl]-benzonitrile. 1H NMR (DMSO-dbeta, 400 MHz) delta 9.25 (s, IH), 8.71 (m, IH), 8.62 (m, 2H), 8.51 (m, 2H), 8.08 (d, 2H), 7.90 (m, IH), 7.88 (m, IH), 7.60 (d, 2H), 7.44 (m, 4H); LC-MS calculated for C28H16ClN7O (M+H+) 502.1, found 502.0.

The synthetic route of 32111-21-0 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; IRM LLC; WO2007/120454; (2007); 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. 6863-74-7, name is 6-Chloropyrazine-2-carbonitrile, A new synthetic method of this compound is introduced below., Safety of 6-Chloropyrazine-2-carbonitrile

To a suspension of Raney-Ni (307 mg, 3.59 mmol,) in EtOH (20 ml_) was added 6- chloropyrazine-2-carbonitrile (1 .00 g, 7.17 mmol,) and terf-butoxycarbonyl tert-butyl carbonate (1 .72 g, 7.88 mmol), then the reaction mixture was stirred at room temperature under H2(45psi) for 16 hours. The reaction mixture was filtered through celite and the filtrate was concentrated under reduced pressure to give a residue. The residue was purified by flash silica gel chromatography (eluention with 0-10% Ethyl acetatertetroleum ether gradient) to give tert-butyl N-[(6-chloropyrazin-2-yl)methyl]carbamate (1 .05 g).

The synthetic route of 6863-74-7 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; H. LUNDBECK A/S; KEHLER, Jan; JUHL, Karsten; MARIGO, Mauro; VITAL, Paulo, Jorge, Vieira; JESSING, Mikkel; LANGGARD, Morten; RASMUSSEN, Lars, Kyhn; CLEMENTSON, Carl, Martin, Sebastian; (270 pag.)WO2018/7249; (2018); A1;,
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Pyrazine | C4H4N2 – PubChem

Related Products of 20737-42-2, 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 20737-42-2 as follows.

STEP 2. 3-CHLORO-PYRAZTNE-2-CARBONYL CHLORIDE; [00202 ] 3 -Hydroxy -pyrazine-2-carboxylic acid (154 mg, 1.1 mmol) was dissolved in phosphorus oxy chloride (2 ml) followed by adding one drop of pyridine. The mixture was heated to reflux for 2h. After that, the reaction solution was concentrated under reduced pressure to give 3-chloropyrazine-2-carboxylic acid chlori

According to the analysis of related databases, 20737-42-2, the application of this compound in the production field has become more and more popular.

Reference:
Patent; AMGEN INC.; ALLEN, Jennifer R.; ANDREWS, Kristin L.; FROHN, Michael J.; HARRINGTON, Paul E.; PICKRELL, Alexander J.; RZASA, Robert M.; WO2011/143129; (2011); 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. 56423-63-3, name is 2-Bromopyrazine, A new synthetic method of this compound is introduced below., Quality Control of 2-Bromopyrazine

To a reaction flask were added compound 21 (100 mg, 0.186 mmol), 2-bromopyrazine (50 mg, 0.279 mmol), Pd(dppf)Cl2 (5 mg, 0.006 mmol) and sodium carbonate (60 mg, 0.558 mmol), 5 mL glycol dimethyl ether and 0.9 mL water were added, bubbled with nitrogen gas for 10 minutes, and the reaction was heated to 100 C in microwave and reacted for half an hour. After TLC detected the reaction was complete, the reaction was concentrated, purified by silica gel column chromatography to afford 72 mg of a product, yield: 79.1%. LC-MS(APCI): m/z = 489.7 (M+1)+. 1H NMR (400 MHz, CDCl3) delta 8.77 (d, J = 2.2 Hz, 1H), 8.71 (s, 1H), 8.63 (s, 1H), 8.52 (d, J = 2.4 Hz, 1H), 8.09 (d, J = 2.3 Hz, 1H), 8.00 (s, 1H), 7.69 (d, J = 9.0 Hz, 2H), 7.23 (d, J = 8.8 Hz, 2H), 3.45 – 3.36 (m, 1H), 3.27 (dt, J = 20.1, 8.5 Hz, 3H), 2.75 – 2.66 (m, 1H), 2.23 (s, 6H), 2.06 (dd, J = 11.1, 5.1 Hz, 1H), 1.85 – 1.74 (m, 1H).

The synthetic route of 56423-63-3 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Shenzhen Targetrx, Inc.; WANG, Yihan; ZHAO, Jiuyang; AL, Yixin; (55 pag.)EP3553056; (2019); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 143591-61-1,Some common heterocyclic compound, 143591-61-1, name is 3-Bromo-8-chloroimidazo[1,2-a]pyrazine, molecular formula is C6H3BrClN3, 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.

Example 13 – N-fS-fS-fCvclohexylamino^midazop^-alpyrazin-S-ypphenvpacetamide (Compound 165)[00260] 3-Bromo-8-bromo/chloroimidazo[l,2-a]pyrazine (200 mg, 0.86 mmol) was combined with JV,iV-diisopropylethylamine (750 uL, 4.3 mmol), cyclohexylamine (1.97 mL, 17.2 mmol) and THF (4 mL) and the mixture heated in a sealed tube at 7O C for 16 hours. In a separate reaction, 3-bromo-8-chloroimidazo[l,2-a]pyrazine (200 mg, 0.86 mmol) was combined with N,N-diisopropylethylamine (750 uL, 4.3 mmol), cyclohexylamine (0.49 mL, 4.3 mmol) and THF (4 mL) and the mixture heated in a sealed tube at 7O C for 16 hours. The reactions were worked up separately. Upon cooling, the reaction mixtures were partitioned between DCM and water and the orgranic extract washed with water and brine, dried over MgSO4, and concentrated in vacuo. The crude products were then combined and purified by column chromatography (EtO Ac/petroleum ether) to give 3-bromo-N-cyclohexylimidazo [l,2-a]pyrazin-8-amine (372 mg, 73%). LCMS RT= 1.66min, MH+ 296.9. 1U NMR (d6- DMSO): 7.45-7.47 (2H, m), 7.38 (IH, d, J4.8), 5.85-7.87 (IH, m), 4.10 (IH, m), 2.10-2.16 (2H, m), 1.77-1.84 (2H, m), 1.62-1.72 (IH, m), 1.26-1.52 (5H, m).

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 3-Bromo-8-chloroimidazo[1,2-a]pyrazine, its application will become more common.

Reference:
Patent; BioMarin IGA, Ltd.; WREN, Stephen Paul; WYNNE, Graham Michael; LECCI, Cristina; WILSON, Francis Xavier; PRICE, Paul Damien; MIDDLETON, Penny; WO2010/69684; (2010); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 36070-80-1, A common heterocyclic compound, 36070-80-1, name is 5-Chloropyrazine-2-carboxylic acid, molecular formula is C5H3ClN2O2, 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.

Example 56 2 (R)- (3-CHLORO-4-METHANESULFONYL-PHENYL)-3-CYCLOPENTYL-N- [5- (2-HYDROXY-1- HYDROXYMETHYL-ETHOXY)-PYRAZIN-2-YL]-PROPIONAMIDE [000288] A suspension of 5-chloro-pyrazine-2-carboxylic acid (prepared as in Example 29,1. 00 g, 6.33 mmol) in methylene chloride (30 mL) was treated with 1,3- dibenzyloxy-2-propanol (2.06 g, 7.57 MMOL), bis (2-oxo-3-oxazolidinyl) phosphinic chloride (1.61 g, 6.34 mmol), and triethylamine (1.83 mL, 12.66 mmol). The mixture was stirred at 25C overnight. The solution was extracted with methylene chloride and a saturated sodium bicarbonate solution. The organic layer was washed with water, a saturated aqueous sodium chloride solution, a 1N hydrochloric acid solution and a saturated aqueous sodium chloride solution. The organic layer was dried over sodium sulfate, filtered, and concentrated in vacuo. Biotage chromatography (FLASH 40L, Silica, 3/1 hexanes/ethyl acetate) afforded the 5-chloropyrazine-2-carboxylic acid 2- BENZYLOXY-1-BENZYLOXYMETHYL-ETHYL ester (1.45 g, 55.7%) as a colorless oil.

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

Related Products of 14399-37-2, A common heterocyclic compound, 14399-37-2, name is 3,6-Dichloropyrazin-2-amine, molecular formula is C4H3Cl2N3, 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.

Stage A: preparation of 5,8-dichlorimidazo[1,2-a]pyrazine This derivative is obtained according to a technique identical to that of Example 1, stage A, by replacing 2-aminopyrazine by 2-amino-3,6-dichloropyrazine. 2.4 grams (18.6 mmol) of this compound yield 1 g (Yld=37%) of 5,8-dichloroimidazo[1,2-a]pyrazine (m.p. 102 C.).

The synthetic route of 14399-37-2 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; l’Universite de Montpellier I; US5028605; (1991); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 21943-17-9, name is 5-Bromo-3-chloropyrazin-2(1H)-one, 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 21943-17-9, Recommanded Product: 5-Bromo-3-chloropyrazin-2(1H)-one

4.3.20 3,5-Bis-(4-methoxyphenyl)-1H-pyrazin-2-one 57 A solution of 56 (50.6 mg, 0.242 mmol), sodium carbonate (35.6 mg, 0.336 mmol), 4-methoxyphenylboronic acid (182 mg, 1.20 mmol) and tetrakis(triphenylphosphine)palladium (0) (17 mg, 0.015 mmol) in water (0.7 mL) and acetonitrile (2.7 mL) was heated in a microwave reactor using variable wattage to 150 C for 20 min. The mixture was partitioned between ethyl acetate (50 mL) and water (40 mL). The organic layer was filtered through a plug of silica gel (6 g). The filtrate was concentrated and purified by flash column chromatography on silica, eluting with ethyl acetate to give 57 (73 mg, 47%). Mp >300 C; Rf (EtOAc) 0.16; numax (thin film/cm-1) 3019 (Ar CH), 1653 (C=O), 972 (C-O), 929 (C–O); deltaH (500 MHz; CD3OD) 3.85 (3H, s, OCH3), 3.88 (3H, s, OCH3), 7.01 (2H, d, J 8.0 Hz, ArH), 7.02 (2H, d, J 9.0 Hz, ArH), 7.66 (1H, s, 6-H), 7.86 (2H, d, J 8.0 Hz, ArH), 8.46 (2H, d, J 9.0 Hz, ArH); LC-MS (6 min) m/z 309 (MH+); HPLC tR 4.11 min; purity 99%; HRMS (found: m/z 309.1243; C18H17N2O3 requires 309.1234).

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-Bromo-3-chloropyrazin-2(1H)-one, other downstream synthetic routes, hurry up and to see.

Reference:
Article; Caldwell, John J.; Veillard, Nicolas; Collins, Ian; Tetrahedron; vol. 68; 47; (2012); p. 9713 – 9728,16;; ; Article; Caldwell, John J.; Veillard, Nicolas; Collins, Ian; Tetrahedron; vol. 68; 47; (2012); p. 9713 – 9728;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem