Month: April 2021

Electric Literature of 23611-75-8,Some common heterocyclic compound, 23611-75-8, name is Methyl 6-chloropyrazine-2-carboxylate, molecular formula is C6H5ClN2O2, 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 methyl 6-chloropyrazine-2-carboxylate (2.50 g, 14.49 mmol) in THF (50 mL) was added methylmagnesium bromide 3M in diethyl ether (12.07 mL, 36.2 mmol) at 0 C. The resulting mixture was stirred at ambient temperature for 30 minutes. The reaction mixture was diluted with saturated NH4Cl (100 mL) and extracted with ethyl acetate (3 x 100 mL). The combined organic layers were washed with brine (50 mL), dried over anhydrous sodium sulfate and concentrated under reduced pressure. The residue was purified by column chromatography (Redisep-24 g, 0.40 % EtOAc/n-hexane) to obtain Intermediate 105A (0.70 g, 28.00%). 1H NMR (400 MHz, DMSO-d6) delta ppm 1.44 (s, 6 H), 5.58 (br,s 1 H), 8.66 (s, 1 H), 8.86 (s, 1 H). LCMS: The compound did not ionize well.

The synthetic route of 23611-75-8 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; BRISTOL-MYERS SQUIBB COMPANY; YADAV, Navnath Dnyanoba; BHIDE, Rajeev S.; BORA, Rajesh Onkardas; GUNAGA, Prashantha; PANDA, Manoranjan; PRIESTLEY, Eldon Scott; RICHTER, Jeremy; (444 pag.)WO2018/222795; (2018); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 4774-14-5, 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. 4774-14-5, name is 2,6-Dichloropyrazine, This compound has unique chemical properties. The synthetic route is as follows.

Example B-10: Preparation of (2S)-1-(4-(1-isopropyl-3-(5-methyl-5H-pyrrolo[3,2-b]pyrazin-2-yl)-1H- pyrazol-4-yl)pyrimidin-2-ylamino)propan-2-ol (B-10) cr Et3NB-10-1 B-10-2 B-10-3Preparation of 6-chloropyrazin-2-amine (B-10-2). B-10-1 B-10-2A mixture of 2,6-dichloropyrazine (300 g, 2 mol) and 28% aq. NH3 (8 L) was stirred at 14O0C in a sealed system for 14 hours. TLC (petroleum ether/EtOAc 3:1 ) indicated complete consumption of starting material. The reaction mixture was extracted with EtOAc (3 L x 3). The combined organic layers were washed with saturated aqueous NaCI (3 L), dried over Na2SO4 and concentrated in vacuo to give crude compound B-10-2, which was purified by column chromatography (silica gel, petroleum ether/EtOAc 2:1) to yield pure compound B-10-2 (410 g, yield: 59.7%) as a white solid.

The chemical industry reduces the impact on the environment during synthesis 2,6-Dichloropyrazine. I believe this compound will play a more active role in future production and life.

Reference:
Patent; PFIZER INC.; WO2009/16460; (2009); A2;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 55557-52-3, These common heterocyclic compound, 55557-52-3, name is 3-Chloropyrazine-2-carbonitrile, 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.5 Synthesis of pyrazine-2-carboxylic acid derivativesA.5.1 Synthesis of pyrazine-2-carbonitrile derivativesA mixture of the respective boronic acid derivative (B-B(OH)2) (21.5 mmol), 3-chloro- pyrazine-2-carbonitrile (21.5 mmol), a solution of K2CO3 (59.4 mmol) in water (30 ml_), PPh3 (3. 2 mmol), Pd(OAc)2 (1.05 mmol) in dry DME was stirred at reflux under inert atmosphere for 16 h. After cooling to rt, the reaction mixture was diluted with EtOAc, filtered over celite, the filtrate was dried over MgSO4, filtered and concentrated in vacuo to yield the desired pyrazine-2-carbonitrile derivative which was used for the next step without further purification3-m-Tolyl -pyrazine-2-carbonitrile prepared by reaction with commercially available 3-m-tolyl-boronic acid LC-MS: tR = 0.88 min; [M+H+MeCN]+ = 243.63

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

Reference:
Patent; ACTELION PHARMACEUTICALS LTD; AISSAOUI, Hamed; BOSS, Christoph; BROTSCHI, Christine; GABILLET, Jerome; SIEGRIST, Romain; SIFFERLEN, Thierry; WILLIAMS, Jodi T.; WO2010/38200; (2010); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

6863-73-6, name is 3-Chloropyrazin-2-amine, 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. Safety of 3-Chloropyrazin-2-amine

A mixture of bromoacetaldehyde diethyl acetal (29 ml,192.77 mmol) and 48% aqueous hydrogen bromide solution (7 ml)was stirred at reflux temperature for 1.5 h. After cooling back toroom temperature it was poured onto a suspension of sodiumhydrogen carbonate (14.50 g, 172.62 mmol) and 2-propanol(230 ml) and stirred until the gas evolution ceased. The formedprecipitate was filtered, then 2-amino-3-chloropyrazine (8) (7.51 g,58 mmol) was added to the filtrate and stirred at reflux temperaturefor 3 h. The reaction mixture was allowed to cool down toroom temperature, the resulting solid was collected by filtrationand washed with 2-propanol. The solid was partitioned betweenchloroform and 10% aqueous sodium hydrogen carbonate solution.The layers were separated and the aqueous layer was extractedwith chloroform (2). The combined organic layers were dried oversodium sulphate, filtered and concentrated under reduced pressure.The crude product was triturated with diisopropyl ether andfiltered to give the title compound (6.48 g)

The synthetic route of 6863-73-6 has been constantly updated, and we look forward to future research findings.

Reference:
Article; Garamvoelgyi, Rita; Dobos, Judit; Sipos, Anna; Boros, Sandor; Illyes, Eszter; Baska, Ferenc; Kekesi, Laszlo; Szabadkai, Istvan; Szantai-Kis, Csaba; Keri, Gyoergy; Oerfi, Laszlo; European Journal of Medicinal Chemistry; vol. 108; (2016); p. 623 – 643;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

These common heterocyclic compound, 762240-92-6, name is 3-(Trifluoromethyl)-5,6,7,8-tetrahydro-[1,2,4]triazolo[4,3-a]pyrazine hydrochloride, 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. Recommanded Product: 3-(Trifluoromethyl)-5,6,7,8-tetrahydro-[1,2,4]triazolo[4,3-a]pyrazine hydrochloride

General procedure: To the stirred reaction mixture of 3-(trifluoromethyl)-5,6,7,8-tetrahydro-1,2,4-triazolo-[4,3-a]pyrazine hydrochloride(11) (300 mg, 1.32 mmol), TEA (0.55 mL, 3.95 mmol)and toluene (10 mL), substituted cyanates 12(a-e)/isocyanates12(f-j) (1.32 mmol) were added at ambient temperature.The reaction mass was agitated at 75-80 C until thecompletion of the reaction that was monitored by TLC. Thereaction mass was allowed to cool at ambient temperatureand it was washed sequentially with 3% aqueous HCl(5.0 mL) and then water (5.0 mL). The organic fraction wasconcentrated under vacuum at 50-55 C to obtain crudeproduct. It was purified by column chromatography using10-50% of EtOAc:hexane mixture as a mobile phase.

The synthetic route of 3-(Trifluoromethyl)-5,6,7,8-tetrahydro-[1,2,4]triazolo[4,3-a]pyrazine hydrochloride has been constantly updated, and we look forward to future research findings.

Reference:
Article; Mannam, Madhava Rao; Devineni, Subba Rao; Pavuluri, Chandra Mouli; Chamarthi, Naga Raju; Kottapalli, Raja Sekhara P.; Phosphorus, Sulfur and Silicon and the Related Elements; vol. 194; 9; (2019); p. 922 – 932;,
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

5-methylpyrazine acid (0.27 mmol, prepared as Example 2), EDCI (0.35mmol) And DMAP (0.027 mmol) were dissolved in dry methylene chloride (20 mL). The compound hederagenin alcohol (140 mg, 0.27 mmol, prepared as Example 3) was dissolved in dichloromethane (20 mL). This solution was dropped into the 5-methylpyrazine acid solution within 20 minutes, and stirred at room temperature for 12 hours. The reaction mixture was then diluted with dichloromethane (20 mL), washed with saturated aqueous NaCl solution, dried over anhydrous sodium sulfate, and purified by column chromatography to obtain a white powder, H-09. Yield: 55% (after chromatograph with DCM / MeOH, 1% -2%) as a white powder, m.p .: 192.6 C.

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

Reference:
Patent; Xinhuo Zhiyao (Beijing) Technology Co., Ltd.; Fang Kang; Guo Wenbo; Wang Penglong; Cheng Gang; (26 pag.)CN110964078; (2020); A;,
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. 5900-13-0, name is 5-Bromo-3-methoxypyrazin-2-amine, A new synthetic method of this compound is introduced below., Application In Synthesis of 5-Bromo-3-methoxypyrazin-2-amine

3,4-dichlorophenyl-methanesulfonyl chloride (2.4 mmol, 650 mg) was added to a solution of 5-bromo-3-methoxypyrazine-2-ylamine (2 mmol, 410 mg) and pyridine (5 mmol, 411 microliter). The mixture was stirred for 72 hours and then partitioned between ethyl acetate, water and acetic acid. The organic phase was collected and evaporated and the residue was crystallized from ethyl acetate and heptane to afford the intermediate N- (5-bromo-3-methoxypyrazine-2-yl)-3,4-dichlorophenyl-methanesulfonamide (1.1 mmol, 470 mg). This was dissolved in dichloromethane (2 mL), cooled on an ice-bath, and boron tribromide (1 M solution in dichloromethane, 2 mmol) was added. The mixture was stirred for 3 hours, then poured onto NaHC03(s)/ice and stirred for additional 3 hours. The precipitate was collected and dissolved in hot ethanol (99.5%), the mixture was filtered while hot, and water was added to the filtrate. The precipitate was collected to afford the title compound (175 mg, 20%)

The synthetic route of 5900-13-0 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; ACTIVE BIOTECH AB; FRITZSON, Ingela; LIBERG, David; EAST, Stephen; MACKINNON, Colin; PREVOST, Natacha; WO2014/184234; (2014); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 16298-03-6, 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. 16298-03-6, name is Methyl 2-aminopyrazine-3-carboxylate belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below.

Example 58; Step 1; A solution of bromine (10 mL, 190 mmol) in acetic acid (10 mL) was added dropwise to a solution of 1 (20 g, 130 mmol) in glacial acetic acid (100 mL) at 45 C. The resulting mixture was stirred at 25 C. for 30 min. After completion of reaction (reaction progress was monitored by TLC), the solution was diluted with water (600 mL) and then stirred at RT for another 30 min. A yellow solid precipitated out, which was filtered, washed with water and dried to afford compound 2 as yellow solid (28.5 g, 93%). MS m/z (ES): 232 (M+H)+.

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 2-aminopyrazine-3-carboxylate, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; de Vicente Fidalgo, Javier; Hermann, Johannes Cornelius; Lemoine, Remy; Li, Hongju; Lovey, Allen John; Sjogren, Eric Brian; Soth, Michael; US2011/59118; (2011); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

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 54608-52-5 as follows. category: Pyrazines

50ml three-necked flask, add 0.2g of compound 6, 15ml of methylene chloride and 15ml of ethyl acetate, after stirring to dissolve,0.3 g of compound 4 and 3 g of T 3 P and 0.75 g of DIPEA were added at 0 C. The system was stirred at 0 C. for 30 min to carry out the reaction until the reaction junctionAfter the beam was added 50ml of dichloromethane and 30ml of water, liquid separation, the organic phase evaporated to give crude compound 7, the crude product is not purified directly down vote;

According to the analysis of related databases, 54608-52-5, the application of this compound in the production field has become more and more popular.

Reference:
Patent; Guangzhou Wenhao Biological Technology Co., Ltd.; Chen Xinying; Xu Liang; Liu Wenzhong; (7 pag.)CN106831731; (2017); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 36070-75-4,Some common heterocyclic compound, 36070-75-4, name is 5-Chloropyrazine-2-carbonitrile, molecular formula is C5H2ClN3, 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 mixture of methyl (R)-3-(3-amino-4-(isobutyl(tetrahydro-2H-pyran-4-yl)amino)phenyl) butanoate (220 mg, 0.63 mmol), 5-chloropyrazine-2-carbonitrile (177 mg, 1 .27 mmol), Pd2(dba)3 (58 mg, 0.064 mmol), Xantphos (74 mg, 0.13 mmol) and K2C03 (262 mg, 1 .9 mmol) in toluene (10 mL) was stirred at 100C under N2 atmosphere overnight. The resulting mixture was partitioned between EtOAc and H2O. The organic layer was washed with brine, dried over Na2S04, filtered and concentrated to give the crude product which was purified by flash chromatography (silica gel, 0-40% EtOAc in PE) to afford the title compound (70 mg, 25% yield). LCMS (ESI) m/z calcd for C25H33N5O3: 451 .26. Found: 452.46 (M+1)+.

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

Reference:
Patent; GLAXOSMITHKLINE INTELLECTUAL PROPERTY DEVELOPMENT LIMITED; DE LA ROSA, Martha Alicia; KAZMIERSKI, Wieslaw Mieczyslaw; SAMANO, Vicente; (369 pag.)WO2018/116107; (2018); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem