Month: May 2021

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. 63286-28-2, name is 2-Chloro-3-hydrazinylpyrazine, This compound has unique chemical properties. The synthetic route is as follows., Quality Control of 2-Chloro-3-hydrazinylpyrazine

General procedure: To a vigorously stirred mixture of alpha-bromonitroalkane (0.50 mmol), heteroaryl hydrazine (0.60 mmol, 1.2 equiv), potassium iodide (1.0 mmol, 2.0 equiv) and potassium carbonate (1.0 mmol, 2.0 equiv) in 1,2-dimethoxyethane (5.0 mL) was added a solution of urea hydrogen peroxide in 1,2-dimethoxyethane/water (4:1) (0.50 M solution, 1.0 mL, 0.50 mmol, 1.0 equiv) over 2 h via syringe pump at r.t. After the addition was complete, the mixture was stirred for an additional 4 h. Aqueous sodium thiosulfate was then added and the mixture was extracted with ethyl acetate. The combined organic layers were washed with brine, dried over sodium sulfate, and concentrated in vacuo. The residue was purified by flash column chromatography to give pure fused triazole.

According to the analysis of related databases, 63286-28-2, the application of this compound in the production field has become more and more popular.

Reference:
Article; Tokumaru, Kazuyuki; Bera, Kalisankar; Johnston, Jeffrey N.; Synthesis; vol. 49; 20; (2017); p. 4670 – 4675;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 33332-25-1, 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. 33332-25-1, name is Methyl 5-chloropyrazine-2-carboxylate belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below.

1.4.1 Intermediate 12(S)-Methyl 5-(3-methoxypyrrolidin- l -yl)pyrazine-2-carboxylate To a solution of methyl 5-chloropyrazine-2-carboxylate ( 1 g, 5.8 mmol) in dry acetonitriie (7.2 mL) was added (S)-3-methoxypyrrolidine hydrochloride ( 1 g, 7.5 mmol) and diisopropylethylamine (3 mL, 17.4 mmol). The reaction vial was sealed and heated under microwave conditions at 140 C for 30 minutes. The reaction mixture was partitioned between EtOAc (50 mL) and sodium carbonate (sat soln.) (50 mL). The organics were further extracted with EtOAc (50 mL). The combined organics were washed with water (2 x 50 mL), brine (50 mL), dried over MgS04, filtered and concentrated to give a pale brown oil which crystallised. The crude solid was purified using chromatography on silica using 0- 10% methanol in EtOAc to give (S)-methyl 5-(3-methoxypyrrolidin-l-yl)pyrazine-2-carboxylate (l .lg, 75%). NMR (400 MHz, DMSO-d6) delta 8.66 (s, 1H), 8.05 (s, 1H), 4.06 – 4.18 (m, 1H), 3.81 (s, 3H), 3.55 – 3.73 (m, 3H), 3.43 – 3.54 (m, 1H), 3.28 (s, 3H), 1.98 – 2.20 (m, 2H). MS ES+ 238

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

Reference:
Patent; TAKEDA PHARMACEUTICAL COMPANY LIMITED; POONI, Parminder, Kaur; MERCHANT, Kevin, John; MAINE, Stephanie, Anne; FIELDHOUSE, Charlotte; SHOWELL, Graham, Andrew; WO2011/83315; (2011); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 768-05-8, A common heterocyclic compound, 768-05-8, name is Pyrazinoic acid hydrazide, molecular formula is C5H6N4O, 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: To a stirred solution of the acid hydrazide 5 (2mmol, 0.27g) in absolute ethanol (10ml), the appropriate heteroaromatic ketone or substituted pyrazolaldehyde (2mmol) was added in the presence of catalytic amount of glacial acetic acid (5 drops), the mixture was refluxed for 12-16h. The product obtained was filtered, washed with diethyl ether, dried and recrystallized from ethanol.

The synthetic route of 768-05-8 has been constantly updated, and we look forward to future research findings.

Reference:
Article; Hassan, Nayera W.; Saudi, Manal N.; Abdel-Ghany, Yasser S.; Ismail, Azza; Elzahhar, Perihan A.; Sriram, Dharmarajan; Nassra, Rasha; Abdel-Aziz, Marwa M.; El-Hawash, Soad A.; Bioorganic Chemistry; vol. 96; (2020);,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

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. 4430-75-5, name is Octahydro-2H-pyrido[1,2-a]pyrazine belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below. Safety of Octahydro-2H-pyrido[1,2-a]pyrazine

1-fluoro-2-nitrobenzene (1.2 g, 8.56 mmol),Octahydro-1H-pyrido[1,2-a]pyrazine (1.0 g, 7.13 mmol), N,N-diisopropylethylamine (1.9 mL, 10.7 mmol) was added to N,N-dimethyl In formamide (20 mL),The reaction was heated to 90 C under nitrogen for 4 hours.After completion of the reaction, the mixture was cooled to room temperature, and the reaction mixture was diluted with water (80 mL)The organic phases were combined and washed successively with water (50 mL) and brine (50 mL).Dry over anhydrous sodium sulfate, and distill off the solvent under reduced pressure.The resulting crude product was purified by silica gel column chromatography (petroleum ether: ethyl acetate (V: V) = 5: 1) to give further title compound (yellow oil, 1.74g, 93.4%).

The synthetic route of 4430-75-5 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Guangdong Dongyangguang Pharmaceutical Co., Ltd.; Jin Chuanfei; Du Changfeng; Zhang Yingjun; (29 pag.)CN108409729; (2018); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 54608-52-5, A common heterocyclic compound, 54608-52-5, name is 2-Hydrazinopyrazine, molecular formula is C4H6N4, 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: p-methylbenzenesulfonic acid (1.7 mg, 0.01 mmol) was added to pyrrole-2-carboxaldehyde derivative 3a (50 mg, 0.406 mmol) and 1-(pyrazin-2-yl)hydrazine (44.7 mg, 0.406 mmol) in 1,2-dichloroethane (50 mL). The reaction mixture was refluxing for 4 h. Then, 0.5 ml of NEt3 was added into the mixture. The reaction mixture was stirred for 10 minutes before subsequent addition of BF3*OEt2 (0.5 mL), and the reaction was left stirring at refluxing condition for 4 h. After cooling to room temperature, the reaction mixture was added CH2Cl2 (50 mL) and poured into water (50 mL). The organic phase was isolated and the corresponding water phase was extracted twice with CH2Cl2 (30 mL). Organic layers were combined, washed with water, dried over anhydrous sodium sulfate, filtered. After solvent removal by evaporation, the crude product was purified by silica gel column chromatography (CH2Cl2/n-hexane = 2:1) to afford 2a (51.7 mg, 41%) as yellow solids.

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; Jiang, Xindong; Yue, Shuai; Chen, Kepeng; Shao, Zhumei; Li, Chen; Su, Yajun; Zhao, Jianzhang; Chinese Chemical Letters; vol. 30; 12; (2019); p. 2271 – 2273;,
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. 5521-55-1, name is 5-Methylpyrazine-2-carboxylic acid, A new synthetic method of this compound is introduced below., COA of Formula: C6H6N2O2

Example 348 W-{[1 -Ethyl-4-(tetrahydro-2H-pyran-4-ylamino)-6-(trif luoromethyl)-1 H- pyrazolo[3,4-Jb]pyridin-5-yl]methyl}-5-methyI-2-pyrazinecarboxamide5-Methyl-2-pyrazinecarboxylic acid (152mg, 1.1mmol, commercially available from e.g. Avocado) was suspended in dichloromethane (3ml) and treated at 200C under nitrogen with oxalyl chloride (0.288ml, 3.3mmol) and diethylformamide (1drop). A vigorous reaction occurred. After 30min the reaction mixture was evaporated to dryness to give a dark yellow oil which was presumed to be 5-methyl-2-pyrazinecarbonyl chloride.A solution of 5-methyl-2-pyrazinecarbonyl chloride (1.1mmol) in dichloromethane (2ml) was added under nitrogen at 2O0C to a stirred mixture of Intermediate 36 (0.343g, 1.Ommol) and diisopropylethylamine (0.77ml, 4.4mmol) in chloroform (7ml). The resulting solution was stirred at 200C under nitrogen for 1.5h. The reaction mixture was evaporated to dryness and the residual oil was dissolved methanol (5ml) and applied to an aminopropyl SPE cartridge (2Og). The cartridge was eluted with methanol (3 column volumes). The product-containing fraction was evaporated to give the crude product as a brown foam (0.403g). This foam was dissolved in dichloromethane (10ml) and applied to a silica SPE cartridge (2Og). The cartridge was eluted using initially a gradient of 0 to 100% ethyl acetate in cyclohexane followed by a gradient of 0 to 20% methanol in ethyl acetate/dichloromethane. The product-containing fraction was evaporated to give Example 348 as a fluorescent yellow solid (0.215g). LCMS showed MH+ = 464; TREtau = 3.23min.

The synthetic route of 5521-55-1 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; GLAXO GROUP LIMITED; WO2007/36733; (2007); 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. 69214-33-1, name is 8-Chloroimidazo[1,2-a]pyrazine, This compound has unique chemical properties. The synthetic route is as follows., Quality Control of 8-Chloroimidazo[1,2-a]pyrazine

?/-(3-(Trifluoromethyl)phenyl)imidazor 1 ‘,2′-alpyrazin-8’-amine (Compound 175) [00238] 3-(Trifluoromethyl)aniline (525 mg, 3.256 mmol) was added to a suspension of sodium hydride (130 mg, 3.256 mmol – 60% in mineral oil) in DMSO (2 mL) and the resulting mixture was stirred under nitrogen atmosphere for 15 minutes. A solution of 8- chloroimidazo[l,2-a]pyrazine (250 mg, 1.628 mmol) in DMSO (2 mL) was then added and stirring continued for another 2 hours. The reaction mixture was then quenched with NH4Cl (sat. aq.) and the product extracted into EtOAc. The organic layer was dried, concentrated in vacuo and purified by flash column chromatography (gradient 2:1 to 3:2 EtOAc:40-60 petrol) to give the title compound (285 mg, 63%). LCMS RT = 6.48 min, MH+ 279. 1H NMR (d6- DMSO): 9.99 (IH, br s), 8.61 (IH, s), 8.32 (IH, d, J 8.8), 8.07 (IH, d, J4.4), 8.04 (IH, d, J 1.1), 7.67 (IH, d, J 1.1), 7.54 (IH, t, J8.2), 7.47 (IH, d, J4.7), 7.32 (IH, d, J7.8).

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 69214-33-1.

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

55557-52-3, name is 3-Chloropyrazine-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: 55557-52-3

EXAMPLE 5.1 (+-)-3-[(6R,8aS)-6-[2-(3-chlorophenyl)-2H-tetrazol-5-yl]hexahydropyrrolo[1,2-a]pyrazin-2(1H)-yl]pyrazine-2-carbonitrile (+-)-(6R,8aS)-6-[2-(3-chlorophenyl)-2H-tetrazol-5-yl]octahydropyrrolo[1,2-a]pyrazine (40 mg, 0.131 mmol) was mixed with 3-chloropyrazine-2-carbonitrile (23.8 mg, 0.17 mmol) and Et3N (0.1 mL) in THF (1 mL) in a sealed vial and heated at 90 C. for 30 min. The reaction mixture was quenched with water and extracted with DCM. The product was purified by column chromatography with 20% ethyl acetate in hexanes to give the title compound (23.8 mg, 44.5%, yellow foam). 1H NMR (CDCl3), delta (ppm): 8.27 (s, 1H), 8.26 (s, 1H), 8.08 (d, 1H), 8.03 (s, 1H), 7.49 (m, 2H), 4.69 (d, 1H), 4.52 (d, 1H), 3.86 (t, 1H), 3.30 (d, 1H), 3.22 (d, 1H), 3.11 (dd, 1H), 2.32-2.60 (m, 4H), 2.04 (m, 1H), 1.84 (m, 1H).

The synthetic route of 55557-52-3 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; AstraZeneca AB; NPS Pharmaceuticals; US2007/37816; (2007); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

109-08-0, name is 2-Methylpyrazine, 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: 2-Methylpyrazine

General procedure: 4-(Di-2-picolylamino)benzaldehyde (1) (110 mg, 0.36 mmol) and the appropriate methyldiazine derivative (0.72 mmol; 0.36 mmol for 4-methyl-2,6-dipyridin-2-yl-pyrimidine; 0.18 mmol for 4,6-dimethylpyrimidine) were dissolved in anhydrous THF (15 mL). KtBuO (1.44 mmol, 161 mg, 4 eq.) was slowly added at room temperature and the solution was heated under reflux for 15 h. The mixture was allowed to cool and water was added. THF was evaporated and the mixture was extracted with CH2Cl2. The organic layer was dried over MgSO4 and the solvent was removed under vacuum. The crude product was purified by flash chromatography.

The synthetic route of 109-08-0 has been constantly updated, and we look forward to future research findings.

Reference:
Article; Achelle, Sylvain; Rodriguez-Lopez, Julian; Bure?, Filip; Robin-Le Guen, Francoise; Dyes and Pigments; vol. 121; (2015); p. 305 – 311;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 233278-56-3, A common heterocyclic compound, 233278-56-3, name is 5,6,7,8-Tetrahydro[1,2,4]triazolo[1,5-a]pyrazine, molecular formula is C5H8N4, 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.

Parallel preparation of Examples 165-195: To a set of vials containing the chloropyrimidine core from Scheme H (25 mg, 0.056 mmol) in DMSO (0.3 mL) was individually added the requisite amine (0.067 mmol) and diisopropylethylamine (0.039 mL, 0.223 mmol). The vials were capped and the mixtures were heated to 1 10C with stirring for 3 hours. The mixtures were cooled to RT. Water (2 mL) was added to each vial. The aqueous phase from each vial was extracted with DCM (2 x 1 mL). The organic layers from each vial were transferred to a clean vial and the solvent was removed in vacuo. To each vial was then added THF:MeOH (1 :3, 1 mL) followed by HCI (4 N in dioxane, 0.20 mL, 0.80 mmol). The vials were capped and the solutions were heated to 70C for 0.5 h. The solutions were allowed to cool to RT and the solvent was then removed from the vials in vacuo. Each crude product was redissolved in 1 mL of DMSO and filtered. The crude products (excluding Example 195) were purified by mass triggered HPLC using the following conditions: [Waters XBridge CI 8 column, 5muiotaeta, 19×100 mm, gradient ranges from 10 initial to 60-70% MeCN (0.1% NH4OH) in water (0.1% NH4OH) 25 mL/min, 8 min run time] to provide the Examplesl65-190. Examples 191-194 were repurified using the following conditions: [Waters Sunfire CI 8 column, 5muetaiota, 19×100 mm, gradient ranges of 10% initial to 70-95% MeCN (0.1% TFA) in water (0.1% TFA) 25 mL/min, 8 min run time]. Example 195 was purified using the following condition: [Waters Sunfire CI 8 column, 5muetaalpha, 19×100 mm, gradient 10% to 50% MeCN (0.1% formic acid) in water (0.1 % formic acid) 25 mL/min, 8 min run time]. Table 11: Parallel preparation of Examples 165-195.

The synthetic route of 233278-56-3 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; MERCK SHARP & DOHME CORP.; MILLER, Michael; BASU, Kallol; DEMONG, Duane; SCOTT, Jack; LI, Wei; STAMFORD, Andrew; POIRIER, Marc; TEMPEST, Paul; WO2014/137723; (2014); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem