Tag: M.W=200-300

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 622392-04-5 as follows. name: 2-Bromo-5-iodopyrazine

EXAMPLE 41C (endo)-3-(5-Iodo-pyrazin-2-yloxy)-8-methyl-8-aza-bicyclo[3.2.1]octane Under N2, the mixture of (endo)-tropine (Aldrich, 1.54 g, 11 mmol) was treated with potassium t-butoxide (Aldrich, 0.96 g, 10 mmol) in THF (anhydrous, Aldrich, 50 mL) at ambient temperature for 1 h. The product of Example 41B (2.85 g, 10.0 mmol) and was added. The brown mixture was stirred at ambient temperature for 4 hours and quenched with water (5 mL). The mixture was concentrated and the residue was purified by chromatography (150 g SiO2, EtOAc:MeOH:NH3.H2O, 90:10:1, Rf. 0.20) to give the title compound. 1H NMR (300 MHz, CD3OD) delta 2.16-2.60 (m, 8H), 2.84 (s, 3H), 3.78-4.05 (m, 2H), 5.17-5.40 (m, 1H), 8.14 (d, J=1.36 Hz, 1H), 8.42 (d, J=1.36 Hz, 1H) ppm; MS (DCI/NH3) m/z 346 (M+H)+.

According to the analysis of related databases, 622392-04-5, the application of this compound in the production field has become more and more popular.

Reference:
Patent; Ji, Jianguo; Li, Tao; Lynch, Christopher L.; Gopalakrishnan, Murali; US2008/45539; (2008); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

87486-34-8, name is 3,5-Dibromo-1-methylpyrazin-2(1H)-one, 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. name: 3,5-Dibromo-1-methylpyrazin-2(1H)-one

Example 185a 5-Bromo-3-(imidazo[1,2-a]pyridin-7-ylamino)-1-methylpyrazin-2(1H)-one 185a A 100-mL round-bottomed flask equipped with a reflux condenser was charged with imidazo[1,2-a]pyridin-7-amine (665 mg, 5.0 mmol), Cs2CO3 (3.26 g, 10 mmol), 3,5-dibromo-1-methylpyrazin-2(1H)-one (1.86 g, 7.0 mmol), Xantphos (289 mg, 0.50 mmol), Pd2(dba)3 (458 mg, 0.50 mmol), and 1, 4-dioxane (30 mL). After bubbling nitrogen through the mixture for 30 minutes, it was heated at 100°C under nitrogen atmosphere for 16 h. Analysis of the reaction mixture by LCMS showed little starting material remained. The reaction mixture was cooled to room temperature and filtered. The filtrate was diluted with dichloromethane (60 mL) and water (50 mL). The aqueous layer was separated and extracted with dichloromethane (3 * 20 mL). The combined organic layers was dried over Na2SO4, filtered, and concentrated under reduced pressure. The dark residue was purified by silica-gel column chromatography eluting with dichloromethane/methanol (60/1 to 30/1) to afford 185a (700 mg, 44percent) as a light yellow solid. MS-ESI: [M+H]+ 320

The synthetic route of 87486-34-8 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; F.Hoffmann-La Roche AG; CRAWFORD, James John; ORTWINE, Daniel Fred; WEI, BinQing; YOUNG, Wendy B.; EP2773638; (2015); B1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 24241-18-7, 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. 24241-18-7 name is 2-Amino-3,5-dibromopyrazine, 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.

[00195] Step 1 : (Trimethylsilyl)acetylene (1.9 g, 2.7 niL, 18.8 mmol) was added dropwise to a solution of 3,5-dibromopyrazin-2-amine (5.0 g, 19.8 mmol), triethylamine (10.0 g, 13.8 mL, 98.9 mmol), copper (I) iodide (452 mg, 2.37 mmol) and Pd(PPh3)4 (1.14 g, 0.99 mmol) in DMF (25 mL) and the resulting solution stirred at room temperature for 30 min. The reaction was diluted with ethyl acetate and water and the layers separated. The aqueous layer was extracted further with ethyl acetate and the combined organics washed with water, dried over MgS04, and concentrated in vacuo. The mixture was purified via silica gelchromatography (0-15% ethyl acetate/hexanes) to afford 5-bromo-3-((trimethylsilyl) ethynyl)pyrazin-2-amine as a yellow solid (3.99g, 75% yield). ¾ NMR (400 MHz, DMSO- d6) delta 0.30 (s, 9H), 8.06 (s, 1H); MS (ES+) 271.82

At the same time, in my other blogs, there are other synthetic methods of this type of compound, 2-Amino-3,5-dibromopyrazine, and friends who are interested can also refer to it.

Reference:
Patent; VERTEX PHARMACEUTICALS INCORPORATED; CHARRIER, Jean-Damien; BINCH, Haley, Marie; HURLEY, Dennis, James; CLEVELAND, Thomas; JOSHI, Pramod; FANNING, Lev Tyler, Dewey; PINDER, Joanne; O’DONNELL, Michael; VIRANI, Anisa, Nizarali; KNEGTEL, Ronald, Marcellus Alphonsus; DURRANT, Steven, John; YOUNG, Stephen, Clinton; PIERRE-HENRI; KAY, David; REAPER, Philip, Michael; WO2011/143426; (2011); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 951626-95-2,Some common heterocyclic compound, 951626-95-2, name is Ethyl 4-oxo-4,5,6,7-tetrahydropyrazolo[1,5-a]pyrazine-2-carboxylate, molecular formula is C9H11N3O3, 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 ethyl 4-oxo-4,5,6,7-tetrahydropyrazolo[1,5-a]pyrazine-2-carboxylate (30 mg, 0.143 mmol) in acetonitrile (1 mL) was added cesium carbonate (93.4 mg, 0.287 mmol) and benzyl bromide (25.6 muL, 0.215 mmol). The reaction mixture was stirred overnight at 70 C. Upon cooling to room temperature, the cesium carbonate was removed by filtration and the solvent evaporated under reduced pressure to afford crude Intermediate 32. LC-MS: (AA) ES+300.

The synthetic route of 951626-95-2 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Millennium Pharmaceuticals, Inc.; US2011/251184; (2011); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 622392-04-5, name is 2-Bromo-5-iodopyrazine, 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 622392-04-5, SDS of cas: 622392-04-5

To a solution of 2-bromo-5-iodopyrazine (500 mg, 1.76 mmol), phenylacetylene (224 mg, 241 mu, 2.19 mmol, 1.25 equiv.), triethylamine (533 mg, 734 mu, 5.27 mmol, 3 equiv.),bis(triphenylphosphine)palladium (II) chloride (73.9 mg, 0.105 mmol, 0.06 equiv.) and triphenyl-phosphine (13.8 mg, 0.053 mmol, 0.03 equiv.) in 10 ml of THF was added under an Argon atmosphere copper (I) iodide (10.0 mg, 0.053 mmol, 0.03 equiv.). The suspension was warmed to 60C overnight, taken up in 5 ml of ethyl acetate and adsorbed on 4 g of silica.Purification by flash chromatography on silicagel using a 2: 1 ethyl acetate/heptane mixture yielded the title compound as a light brown solid (107 mg, 23% yield). The material was directly used in the next step without further characterization.

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

Reference:
Patent; F. HOFFMANN-LA ROCHE AG; GREEN, Luke; GUBA, Wolfgang; JAESCHKE, Georg; JOLIDON, Synese; LINDEMANN, Lothar; RICCI, Antonio; RUEHER, Daniel; STADLER, Heinz; VIEIRA, Eric; WO2011/128279; (2011); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 32111-21-0,Some common heterocyclic compound, 32111-21-0, name is 2-Iodopyrazine, molecular formula is C4H3IN2, 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 58; N- f 3-[” 1 -(4-Chloro-phenvU-6-oxo-2-( 4-pyrazin-2-yl-phenylV 1.6-dihvdro-purin-9-yll-phenyl – methane sulfonamide; [00193] A solution of N-(3-{l-(4-chloro-phenyl)-6-oxo-2-[4-(4,4,5,5-tetramethyl-[l,3,2]dioxaborolan-2-yl)-phenyl]-l,6-dihydro-purin-9-yl}-phenyl)-methane sulfonamide (preparaed as described in example 26, 0.5 g, 0.809 mmol) in N,N-dimethylformamide (20 mL) is degassed with argon for 0.5 h. Then 2-iodopyrazine (0.25 g, 1.21 tnmol), cesium carbonate (0.527 g, 1.61 mmol), Pd(dppf)2Cl2 (0.059 g, 0.08 mmol) is added and the resulted mixture is degassed with argon for 0.5 h. The reaction mixture is stirred at rt for 18 h. The reaction mixture is poured into water and extracted with ethyl acetate (3 *). The combined organic layer is washed with brine, dried over Na2SO4, concentrated, and purified by column chromatography to afford N-{3-[l-(4-chloro-phenyl)-6-oxo-2-(4-pyrazin-2-yl-phenyl)-l ,6- dihydro-purin-9-yl]-phenyl}-methane sulfonamide. 1H NMR (DMSOd6, 400 MHz) delta 9.25 (s, IH), 8.69 (m, IH), 8.62 (m, 2H), 8.03 (m, 2H), 7.74 (s, IH), 7.46-7.56 (m, 9H), 7.25 (m, IH), 3.05 (s, 3H); LC-MS calculated for C28H20ClN7O3S (M+H4) 570.1, found 569.9.

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

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

Reference of 24241-18-7, 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. 24241-18-7, name is 2-Amino-3,5-dibromopyrazine belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below.

Step A: Preparation of ethyl 6,8-dibromoimidazo[ 1 , 2-a]pyrazine-2-carboxylateTo a stirred solution of 2-amino-3, 5-dibrompyrazine (20 g, 79mmol) in dimethyicarbonate (1 33 mL) at rt was added ethyl 3-bromo-2-oxopropanoate (17.14 g, 79 mmol) in one portion. After stirring at 1 10 C for 3 h, the solution was stirred at rt overnight. Water and DCM were added and the aqueous phase was extracted with DCM. After washing of the organic phase with water, drying over Na2(S04) and filtration the organic phase was evaporated. Flash chromatography yielded 13.95 g (50.6 %) ethyl 6,8-dibromoimidazo[1 ,2-a]pyrazine-2-carboxylate: 1H-NMR (300 MHz, CDC ): delta =8.30 (s, 1 H), 8.27 (s, 1 H), 4.48 (q, 2H), 1 .43 (tr, 3H) ppm.

The synthetic route of 2-Amino-3,5-dibromopyrazine has been constantly updated, and we look forward to future research findings.

Reference:
Patent; BAYER PHARMA AKTIENGESELLSCHAFT; KOPPITZ, Marcus; KLAR, Ulrich; JAUTELAT, Rolf; KOSEMUND, Dirk; BOHLMANN, Rolf; BADER, Benjamin; LIENAU, Philip; SIEMEISTER, Gerhard; WO2012/80228; (2012); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 1458-18-0, A common heterocyclic compound, 1458-18-0, name is Methyl 3-amino-5,6-dichloropyrazine-2-carboxylate, molecular formula is C6H5Cl2N3O2, 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.

PREPARATIVE EXAMPLES Preparative Exam ple1.A round bottomed flask was charged with methyl 6-amino 2,3-dichloro pyrazine 5-carboxylate (Aldrich, 25 g, 112.6 mmol), 2-S-ethyl piperazine (prepared as per Williams et al J. Med. Chem. 1996, 39, 1345, 83% active, 15.7 g, 112.7 mmol), cesium carbonate (100 g, 300 mmol) and 1 ,4 dioxane (400 ml). The flask was equipped with a reflux condenser and heated to8O0C. After 12 hours, the reaction was cooled, diluted with methylene chloride (~ 200 ml), and filtered through celite. The filtrate was washed once with water and then concentrated to an oil. The crude product was purified by silica gel chromatography using a methanol/ methylene chloride eluent (3% to 10% MeOH) to afford 30.8 g (91 %) of compound A3. MS, M+H = 300.

The synthetic route of 1458-18-0 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; SCHERING CORPORATION; PHARMACOPEIA DRUG DISCOVERY, INC.; WO2006/91428; (2006); A2;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 87486-34-8, A common heterocyclic compound, 87486-34-8, name is 3,5-Dibromo-1-methylpyrazin-2(1H)-one, molecular formula is C5H4Br2N2O, 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 100-mL three-neck round-bottomed flask equipped with a mechanical stirrer and reflux condenser was charged with Ik (780 mg, 3.56 mmol), 11 (998 mg, 3.73 mmol), cesium carbonate (2.36 g, 7.26 mmol) and 1,4-dioxane (40 mL). After bubbling nitrogen through the resulting solution for 30 minutes, Xantphos (.162 g, 0.281 mmol) and tris(dibenzylideneacetone)dipalladium(0) (.15 g, .165 mmol) were added, and the reaction mixture was heated at reflux for 16 h. After this time the reaction was cooled to room temperature and concentrated under reduced pressure. The resulting residue was absorbed onto silica gel and purified by flash chromatography to afford a 57percent yield (818 mg) of Im as an orange solid: mp 206- 207 0C; 1U NMR (500 MHz, CDCl3) delta 8.27 (bs, IH), 7.72 (dd, IH, J = 2.0, 8.5 Hz), 7.36 (dd, 2H, J = 2.0, 8.5 Hz), 6.73 (s, IH), 3.71 (m, IH), 3.69 (s, IH), 3.52 (s, 3H), 3.21 (m, IH), 3.01 (m, IH), 2.97 (s, 3H), 2.67 (m, IH), 2.19 (s, 3H); MS (ESI+) m/z 406 (M+H).

The synthetic route of 87486-34-8 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; CGI PHARMACEUTICALS, INC.; GENENTECH, INC.; WO2009/137596; (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. 63744-22-9, name is 6,8-Dibromoimidazo[1,2-a]pyrazine, A new synthetic method of this compound is introduced below., Product Details of 63744-22-9

A mixture of known compound 6 (4.0g, 14.44mmol) (25mL), cyclopropylamine (1.5mL, 21.67mmol) and N, N-diisopropylethylamine (3.8mL, 21.67mL) in 1,4-dioxane was stirred at 80C for 5h. The reaction mixture was cooled to room temperature, diluted with ethyl acetate and washed with saturated aqueous NaHCO3. The organic phase was dried over anhydrous Na2SO4 and filtered. The filtrate was concentrated in vacuo. The residue was purified by column chromatography (Hexanes: EtOAc=1:1) to afford the title compound 8 (3.43g, 94%). 1H NMR (300MHz, DMSO-d6) delta 8.08 (s, 1H), 8.02 (s, 1H), 7.80 (s, 1H), 7.46 (s, 1H), 2.88 (m, 1H), 0.67 (m, 4H).

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; Kang, Seok Jong; Lee, Jung Wuk; Chung, Shin Hyuck; Jang, Sun Young; Choi, Jaeyul; Suh, Kwee Hyun; Kim, Young Hoon; Ham, Young Jin; Min, Kyung Hoon; European Journal of Medicinal Chemistry; vol. 163; (2019); p. 660 – 670;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem