Month: June 2021

17231-51-5, name is 3-Amino-6-bromopyrazine-2-carbonitrile, 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. Recommanded Product: 3-Amino-6-bromopyrazine-2-carbonitrile

Step A Synthesis of 2-amino-3-cyano-5-(trimethylsilylethynyl)pyrazine as an intermediate A solution of 3.0 grams (0.015 mole) of 2-amino-3-cyano-5-bromopyrazine and 2.1 grams (0.021 mole) of trimethylsilylacetylene in 50 mL of acetonitrile is stirred, and 10.6 mL of triethylamine, 0.13 gram of copper iodide, and 0.29 gram of bis(triphenylphosphine)palladium(II) chloride are added in order. Upon completion of addition, the reaction mixture is stirred at ambient temperature for about 20 hours. The reaction mixture is warmed to 70 C., where it is stirred for about 7.5 hours. After this time, the reaction mixture is concentrated under reduced pressure to a residue. The residue is dissolved in ethyl acetate, and the solution is washed with 50 mL of aqueous, dilute hydrochloric acid. The organic layer is dried with magnesium sulfate and filtered. The filtrate is concentrated under reduced pressure to a residue. The residue is subjected to column chromatography on silica gel. Elution is accomplished using tetrahydrofuran/methylene chloride combinations. The product-containing fractions are combined and concentrated under reduced pressure, yielding 2-amino-3-cyano-5-(trimethylsilylethynyl)pyrazine.

The synthetic route of 17231-51-5 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; FMC Corporation; US5521190; (1996); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 24241-18-7, These common heterocyclic compound, 24241-18-7, name is 2-Amino-3,5-dibromopyrazine, 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 stirred suspension of 2-amino-3,5-dibrompyrazine (427 g, 1688mmol) in water (6.4 L) / THF (482 mL), at rt was added bromacetaldehyde-diethylacetal (998 g, 5065 mmol) in one portion. After stirring under reflux for 4 h, the clear orange solution was stirred for an additional 15 h at rt. The suspension was filtered, and the remaining solid was washed with MeOH (2 L) and dried in vaccuo at 60 C to yield 6,8-dibromo-imidazo[1 ,2-a]pyrazine as an off-white solid (500 g, 107% with residual MeOH): 1H-NMR (300 MHz, d6-DMSO): delta =9.02 (s, 1 H), 8.23 (d, 1 H), 7.89 (d, 1 H) ppm. UPLC-MS: RT = 0.80 min; m/z 277.9 [MH+]; required MW = 276.9.

Statistics shows that 2-Amino-3,5-dibromopyrazine is playing an increasingly important role. we look forward to future research findings about 24241-18-7.

Reference:
Patent; BAYER PHARMA AKTIENGESELLSCHAFT; SIEMEISTER, Gerhard; BADER, Benjamin; WENGNER, Antje, Margret; MUMBERG, Dominik; KOPPITZ, Marcus; KLAR, Ulrich; KROEMER, Guido; VITALE, Ilio; JEMAA, Mohamed; WO2014/20041; (2014); 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. 14508-49-7, name is 2-Chloropyrazine, A new synthetic method of this compound is introduced below., name: 2-Chloropyrazine

[Referential Example 33] 2-Hydrazinopyrazine; [Show Image] Hydrazine monohydrate (21.80 g) was added to a solution of 2-chloropyrazine (10.44 g) in ethanol (65 ml) at room temperature, and the mixture was heated under reflux for 17 hours. After cooling with air, the reaction solvent was evaporated under reduced pressure, and benzene was added to the residue, then the insoluble content was’ removed by decantation. After evaporation of the benzene solution under reduced pressure, hexane was added to the resulting solid, and the product was collected by filtration to give the title compound (4.67 g, 47%). 1H-NMR (400 MHz, CDCl3)delta: 7.89 (1H, d, J = 2.7 Hz), 7.99-8.05 (1H, m), 8.20 (1H, d, J = 1.5 Hz). ESI-MSm/z: 111 (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; DAIICHI PHARMACEUTICAL CO., LTD.; EP1698626; (2006); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 14508-49-7, name is 2-Chloropyrazine, 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 14508-49-7, name: 2-Chloropyrazine

Intermediate 65; 4-Pyrazin-2-yl-lH-indole; 4-Bromoindole (0.1 g, 0.51 mmol), bis(pinacolato)diboron (0.172 g, 0.77 mmol), potassium acetate (0.075 g, 0.765 mmol) and PdCl2 (0.022 g, 0.031 mmol) were dissolved in DME (3 mL) and heated in the microwave for 900 seconds at 125C. The reaction was cooled and NaHCO3 (0.129 g, 1.53 mmol), 2-chloropyrazine (0.087 g, 0.77 mmol) tetrakis(triphenylphosphine)palladium (0.0295 g, 0.026 mmol), H2O (1 mL) and DME (1 mL) were added and the mixture was stirred in the microwave for 900 seconds at 120C. The mixture was diluted with dichloromethane and filtered. The filtrate was washed with water (2x), dried (MgSO4) and evaporated. The crude product was purified by flash chromatography using 2.5% to 5% CH3OH in dichloromethane. Not pure, purified by flash chromatography using hexane/EtOAc 7:3 to 1:1 as the eluent. Yield: 93 mg (47%). White solid. MS (electronspray; [M+H]+) m/z 196.3.

If you are interested in these compounds, you can also browse my other articles.Thank you for taking the time to read this article. I hope you enjoyed it.

Reference:
Patent; BIOVITRUM AB (publ); WO2008/3703; (2008); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 6905-47-1, A common heterocyclic compound, 6905-47-1, name is 2-Amino-6-methoxypyrazine, molecular formula is C5H7N3O, 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 solution of 6-methoxypyrazin-2-amine (0.5 g, 4.0 mmol) in CHCI3 (25 mL) was added NCS (533 mg, 4.0 mmol). The reaction mixture was stirred at 40C for 12 h. The mixture was concentrated to give a residue. The residue was purified by column chromatography (Si02) to give 5-chloro-6-methoxypyrazin-2-amine (95 mg, 14.9% yield) as a yellow solid. NMR (400MHz, CHLOROF ORM-f) delta 7.32 (s, 1H), 4.42 (s, 2H), 3.96 (s, 3H).

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; QUENTIS THERAPEUTICS, INC.; VACCA, Joseph P.; LI, Dansu; BETTIGOLE, Sarah; (214 pag.)WO2019/94641; (2019); A1;,
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. 1209646-17-2, name is 5-(4-(tert-Butoxycarbonyl)piperazin-1-yl)pyrazine-2-carboxylic acid, This compound has unique chemical properties. The synthetic route is as follows., Product Details of 1209646-17-2

5-(4-(tert-butoxycarbonyl) piperazin-1 -yl) pyrazine-2-carboxylic acid (200 mg, 0.65 mmol), tert-butyl 2-amino-4-(thiophen-2-yl) phenylcarbamate (157 mg, 0.54 mmol) and EDCI (311 mg, 1.62 mmol) were added into Py (5 ml). The mixture was stirred at room temperature for overnight. When the reaction finished, it was concentrated and washed with Et20. The yellow solid was collected as product (310 mg, 65% yield).

According to the analysis of related databases, 1209646-17-2, the application of this compound in the production field has become more and more popular.

Reference:
Patent; Regenacy Pharmaceuticals, LLC; van Duzer, John H.; Mazitschek, Ralph; (123 pag.)US2018/141923; (2018); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 1458-01-1, name is Methyl 3,5-diamino-6-chloropyrazine-2-carboxylate, 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 1458-01-1, Recommanded Product: 1458-01-1

(b) A mixture of 2.0 g (10.0 mmol) of methyl 3,5-diamino-6-chloropyrazine-2-carboxylate and 13.5 g (22.6 mmol) of ethylene diamine was allowed to stand for 3 days at ambient temperature. The excess amine was evaporated and the residue was crystallized from ethanol. There was obtained 1.38 g (5.9 mmol, 59percent) of 3,5-diamino-6-chloro-N-(2-aminoethyl)pyrazine-2-carboxamide: mp 173°-174° C. Analysis calculated for C7 H11 ClN6 O: C, 36.45: N, 4.81; N, 36.44; Found: C, 36.50; N, 4.71; N, 36.22

At the same time, in my other blogs, there are other synthetic methods of this type of compound, Methyl 3,5-diamino-6-chloropyrazine-2-carboxylate, and friends who are interested can also refer to it.

Reference:
Patent; ICI Americas Inc.; US4906633; (1990); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 642459-03-8,Some common heterocyclic compound, 642459-03-8, name is 6-Chloro-N-phenylpyrazin-2-amine, molecular formula is C10H8ClN3, 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 36 36A. Preparation of Phenyl- [6- (2. 2, 2-triiluoroethoxy-pyrazm-2-yl]-amine To sodium hydride (50 mg, 1.25 mmol of a 60% dispersion in oil, 1.5 equiv) in DMSO (1 ml) was added a solution of 2, 2, 2-trifluoroethanol (90 1ll, 1.25 mmol, 1.5 equiv) in DMSO (1 ml). The mixture was stirred 15 minutes and 6-chloro- (pyrazin- 2-yl) -phenyl-amine (171 mg, 0.833 mmol, 1 equiv) was added as a solution in DMSO (1 ml). The mixture was heated to 80C for 3 days. The title compound was purified by flash chromatography on silica (19 g, Si02), eluted with 25% ethyl acetate-petrol, to afford 110 mg (49%) ; LCMS 3.95 min, [M+H]”270.; 36B. Preparation of (6-Methylsulfanyl-pyrazin-2-yl)-phenyl-amine The title compound was obtained as a side product of the method of 36A and was isolated as a minor fraction of the reaction products following flash chromatography on silica (19 g, Si02), eluting with 25% ethyl acetate-petrol, to afford 3 mg (1%); LCMS 2.76 min, m/z [M+H] + 218.

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

Reference:
Patent; ASTEX TECHNOLOGY LIMITED; WO2004/4730; (2004); A2;,
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. 32587-10-3, name is 3-Aminopyrazine-2-carboxamide, A new synthetic method of this compound is introduced below., category: Pyrazines

To a stirred solution of 3-aminopyrazine-2-carboxamide (1 g, 7.24 mmol, prepared according to International Patent Application Publication No. W0201 1054922) and NaOAc (200mg, 2.44 mmol) in HOAc (15 mE) was added Br2 (0.45 mE) dropwise at 0C for 1 hour, and then it was stirred at 50C for 8 hours. After the mixing, it was poured into ice-water and filtrated, the crude product of 3-amino-6-bromopyrazine-2-carboxamide as brown solid (1.5 g, yield: 95%) was obtained. ?H-NMR (DMSO-d6, 400 MHz) 8.30 (s, 1H), 7.93 (s, 2H), 7.66 (s, 2H). MS (M+H):217/219.

The synthetic route of 32587-10-3 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; MERCK SHARP & DOHME CORP.; DAI, Xing; LIU, Hong; PALANI, Anandan; HE, Shuwen; NARGUND, Ravi; XIAO, Dong; ZORN, Nicolas; DANG, Qun; MCCOMAS, Casey C.; PENG, Xuanjia; LI, Peng; SOLL, Richard; WO2014/205593; (2014); 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. 43029-19-2, name is 3-Aminopyrazin-2(1H)-one, A new synthetic method of this compound is introduced below., HPLC of Formula: C4H5N3O

General procedure: The pyrazin-2(1H)-one base (11a, 14, 19, 20, 21 or 23) (2 mmol)was added in 1,1,1,3,3,3-hexamethyl-disilazane (HMDS, 10 mL) andheated at 120 for 3 h. Then, the solvent was removed in vacuo asmuch as possible and the obtained residue was dissolved or suspendedin DCM (15 mL), followed by the addition of sugar donor (B or C,2.4 mmol, 1.2 eq.). SnCl4 (2.0 mmol, 1.0 eq.) was added dropwise to thesolution in an ice bath and the reaction mixture was stirred overnight atrt. The solution was diluted with DCM (50 mL), washed with water(20 mL×2), dried over Na2SO4 and concentrated in vacuum. Thecrude residue was purified by silica gel column chromatography to giveintermediates 24a-24e and 27a-27c, which were subsequently treatedwith K2CO3 (2 mmol, 2 eq.) in MeOH (15 mL) to give nucleosides 25 a-25e and 28a-28c.

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