Category: 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. 123-32-0, name is 2,5-Dimethylpyrazine, A new synthetic method of this compound is introduced below., 123-32-0

Preparation of 3,6-dimethyl-2- (3-chloro) benzoyl pyrazine, comprising the steps of:(1) 2,5-dimethyl pyrazine take 0.2mmol, 3- chloro-benzoyl formate 0.4mmol, silver phosphate 0.02mmol, potassium persulfate 0.4mmol, 1.4mL was added dichloromethane, 0.6mL distilled water after the mixture was made, and the mixture was placed in a reaction tube in 5mL, placed in an oil bath at 40 heated, the 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 37mg target The product, 74% yield.

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

5049-61-6,Some common heterocyclic compound, 5049-61-6, name is Pyrazin-2-amine, molecular formula is C4H5N3, 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.

Referring to Scheme 3, pyrazin-2-ylamine (1 g, 10.5 mmol) was dissolved in a solution of DMSO (40 ml)/H2O (1 ml) at 0 C. N-bromosuccinimide (3.93 g, 22 mmol) was added over an hour keeping the temperature below 5 C. Once addition was complete, the mixture was stirred for 6 hours at RT. The mixture was poured over ice water (150 ml) whilst stirring, then extracted with EtOAc (4¡Á100 ml). The organic layers were combined, dried and evaporated to leave an orange oil, which solidified overnight under high vacuum. 3,5-dibromopyrazin-2-amine was produced as an orange/brown solid (2.24 g, 84%). The product was used for the next reaction without further purification. [M+H] calc’d for C4H3Br2N3, 254; found, 254.

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

Reference:
Patent; Dong, Qing; Hosfield, David J.; Paraselli, Bheema R.; Scorah, Nicholas; Stafford, Jeffrey A.; Wallace, Michael B.; Zhang, Zhiyuan; US2006/84650; (2006); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

32111-21-0, A common compound: 32111-21-0, name is 2-Iodopyrazine, 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.

Step C: A solution of 5-(4-chloro-phenyl)-l-(3-methanesulfonyl-phenyl)-6-[4-(4,4,5,5-tetramethyl-[l,3,2]dioxaborolan-2-yl)-phenyl]-l,5-dihydro-pyrazolo[3,4-d]- pyrimidin-4-one (8, 0.5 g, 0.829 mmol) in N,N-dimethylformamide (20 mL) is degassed with argon for 0.5 h. Then 2-iodopyrazine (0.26 g, 1.2 mmol), cesium carbonate (0.54 g, 1.7 mmol), Pd(dppf>2Cl2 (0.06 g, 0.08 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 3 h. The reaction mixture is cooled to rt and diluted with water and extracted with ethyl acetate (3 *). The combined organic layer is washed with brine, dried over Na2SO4, concentrated, and purified by preparative HPLC to afford 5-(4-chloro-phenyl)-l-(3-methanesulfonyl-phenyl)-6-(4-pyrazin- 2-yl-phenyl)-l,5-dihydro-pyrazolo[3,4-d]pyrimidin-4-one (9). 1H NMR (DMSO-d6, 400 MHz) delta 9.25 (s, IH), 8.71 (m, IH), 8.68 (m, IH), 8.63 (m, IH), 8.61 (m, IH), 8.55 (m, IH), 8.09 (m, 2H), 7.95 (m, IH), 7.88 (m, IH), 7.62 (m, 2H), 7.45 (m, 4H), 3.30 (s, 3H); LC-MS calculated for C28H19ClN6O3S (M+H*) 555.1, found 555.0.

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-Iodopyrazine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; IRM LLC; WO2007/120454; (2007); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

6270-63-9, A common compound: 6270-63-9, name is Pyrazin-2(1H)-one, 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.

General procedure: The appropriate nucleophile (1 equiv.), the epoxide (1-3 equiv.) and a base (1-5 equiv.) were suspended in a solvent and the reaction mixture was heated under the stated conditions. (0735) The reaction was allowed to cool to rt, saturated NH4CI(aq) or water was added and the resulting mixture was extracted using DCM or EtOAc (x 3). The combined organic extracts were dried (phase separator or MgS04), concentrated under reduced pressure and the remaining residue was purified by flash chromatography to give the product.

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

Reference:
Patent; ALMAC DISCOVERY LIMITED; ROUNTREE, James Samuel Shane; WHITEHEAD, Steven Kristopher; TREDER, Adam Piotr; PROCTOR, Lauren Emma; SHEPHERD, Steven David; BURKAMP, Frank; COSTA, Joana Rita Castro; O’DOWD, Colin; HARRISON, Timonthy; (333 pag.)WO2019/150119; (2019); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

98-97-5, These common heterocyclic compound, 98-97-5, name is Pyrazine-2-carboxylic acid, 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 stirring solution of 372 mg of pyrazine-2-carboxylic acid (3 mmol), 623 mg of (S)-methyl 2-amino-2-cyclohexylacetate (3 mmol), and 2.5 mL of N,N-diisopropyl ethylamine in 25 mL of anhydrous dichloromethane, was added 760 mg of 1,4-dimethyl-2-chloroimidazolium hydrochloride (4.5 mmol) in three portions. The resulting mixture was stirred at RT for additional 30 min, then concentrated under reduced pressure. The residue was re-dissolved into 80 mL of ethyl acetate, and washed with aqueous sodium bicarbonate, brine, and dried over anhydrous sodium sulfate. After concentration, the crude product was purified by flash column chromatography, eluting with heptane/ethyl acetate (v/v 2/1), giving 897 mg of yellowish oil as desired ester.

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 98-97-5.

Reference:
Patent; Avila Therapeutics, Inc.; US2010/41674; (2010); 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. 33332-25-1, name is Methyl 5-chloropyrazine-2-carboxylate, A new synthetic method of this compound is introduced below., 33332-25-1

Preparation of 5-Chloropyrazine-2-carboxylic acid To a flask fitted with overhead stirrer, condenser, thermometer and nitrogen line was added methyl 5-chloropyrazine-2-carboxylate (1.0 eq) and tetrahydrofuran (4.92 vols) under a nitrogen atmosphere. The reaction mixture was agitated until all the solid had dissolved, then filtered into a second flask. Water (8.65 vols) was added to the reaction mixture and the mixture agitated for approximately 15 minutes. Potassium carbonate (2.1 eq) was added to the reaction mixture and the mixture agitated for 16 hours at 20-25 C. Then 32% w/w hydrochloric acid (3.76 eq) was added over 3 hours in small portions, keeping the reaction temperature 20-25 C., to a pH end point of pH2.2. The resultant slurry was heated to approximately 35-40 C. and then distilled under vacuum at this temperature distilling approximately 5.3 vols, to a final volume of approximately 9.3 vols. The mixture was then cooled to 20-25 C. over at least 2 hours, agitated for 10 hours at this temperature and then filtered. The solid was washed with water (2.8 vols), and the wet product produced dried at 35 C. in a vacuum oven. The desired product was obtained as a solid (corrected yield 91%) 1H NMR delta (400 MHz CDCl3): 7.20 (1H, bs), 8.72 (1H, s), 9.21-9.21 (1H, m); m/z 157 (M-H)+.

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; AstraZeneca AB; US2010/210621; (2010); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

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. 5049-61-6

A novel process for the reaction of a secondary amine by reaction of 2-aminopyrazine with triethylamine, comprising the steps of:Under nitrogen protection,Under nitrogen protection,2-aminopyrazine (95 mg, 1 mmol) was added to a 50 mL Schlenk tube,Triethylamine (304 mg, 3 mmol),[(Bt) 2 * Ir * P (nBu) 3] OTf (9.6 mg, 0.01 mmol, 1.0 mol%),Add 2.0mL xylene;The reaction solution was reacted at 155 C for 10 h,The resulting solution was separated on a silica gel column from 200 to 300 mesh (eluent 1:10 ethyl acetate / petroleum ether)After removal of the solvent,To get the product.Yield: 78%.

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, 5049-61-6, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; Jingnan University; Zhang, Songlin; Fan, Huijun; Zhang, Donghui; Wang, Dawei; Ding, Yuqiang; (6 pag.)CN104710257; (2017); B;,
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. 5049-61-6, name is Pyrazin-2-amine, A new synthetic method of this compound is introduced below., 5049-61-6

Pyrazin-2-amine (11.3 g, 118.9 mmol) was dissolved in acetonitrile (100 mL) and Nchlorosuccinimide(NCS, 15.8 g, 118.9 mmol.) was added slowly inportions. Then, the reaction mixture was heated up to 40 and stirreduntil the amount of the main product did not increase anymore. Thesolution was filtered through Celite and the filter cake was washed byEA. The combined filtrate was washed by saturated aqueous NaHCO3solution (30 mL¡Á3) and brine, dried over anhydrous Na2SO4 anddecolorized by active charcoal. The mixture was filtered andconcentrated in vacuo. The precipitate was collected by filtration, andthe filtrate was purified on silica gel. A total of 8.4 g (yield 55%) wasobtained for compound 11b. 1H NMR (400 MHz, CDCl3): delta 8.01 (d, 1H,J=1.4 Hz), 7.76 (d, 1H, J=1.4 Hz), 4.57 (s, 2H).

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:
Article; Guo, Shuang; Xu, Mingshuo; Guo, Qi; Zhu, Fuqiang; Jiang, Xiangrui; Xie, Yuanchao; Shen, Jingshan; Bioorganic and Medicinal Chemistry; vol. 27; 5; (2019); p. 748 – 759;,
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

A 500ml three-neck flask, was added 2-amino pyrazine (19g, 0.2mol), dichloromethane (200ml) and pyridine (50ml) mixed solution at room temperature was slowly added dropwise bromine (67.2g, 0.42mol) in dichloro methane (100ml) solution, stirred at room temperature 4h, the reaction system was added to 100ml of water, stirred for 2h, the organic layer was washed with water (100ml ¡Á 3), the organic phase was moved to a flask with silica gel, and activated charcoal is heated at reflux for 1h, suction , the solvent was distilled off under reduced pressure, the resulting solid was added hexane (45 ml of) and refluxed for 2h and filtered while hot, and dried to give a yellow solid 39.4g, yield 77.8%.

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; Hubei University of Technology; Liu, Mingxing; Jiang, Weidong; Wang, Wanxia; (6 pag.)CN105622526; (2016); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

486460-21-3, A common heterocyclic compound, 486460-21-3, name is 3-(Trifluoromethyl)-5,6,7,8-tetrahydro-[1,2,4]triazolo[4,3-a]pyrazine, molecular formula is C6H7F3N4, 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 26 2-((5-(2-(3,4-dimethoxyphenyl)propan-2-yl)-4-(4-fluorophenyl)-4H-l,2,4-triazol-3- yl)thio)-l-(3-(trifluoromethyl)-5,6-dihydro-[l,2,4]triazolo[4,3-a]pyrazin-7(8H)- yl)ethanone 2-((5-(2-(3,4-dimethoxyphenyl)propan-2-yl)-4-(4-fluorophenyl)-4H-l,2,4-triazol-3- yl)thio)acetic acid and 3-(trifluoromethyl)-5,6,7,8-tetrahydro-[l ,2,4]triazolo[4,3- a]pyrazine was dissolved in DMF and then cooled to 0 C followed by addition of HBTU and DIPEA, reaction was monitored by TLC and then reaction was quenched by water and compound was extracted by ethyl acetate. Product was purified by column chromatography. NMR (DMSO-ck, 400 MHz): 7.10-7.03 (m, 2H), 6.77-6.70 (m, 3H), 6.40 (d, J = 5.6 Hz, 2H), 5.03 (s, 1H), 4.84 (s, 1H), 4.24-4.19 (m, 4H), 4.05-4.00 (m, 2H), 3.72 (s, 3H), 3.60 (s, 3H), 1.53 (s, 6H). m/z Relative intensities: 606.1 (M+)100 %.

The synthetic route of 486460-21-3 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; CADILA HEALTHCARE LIMITED; AGARWAL, Sameer; DESAI, Ranjit, C.; WO2013/164838; (2013); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem