Month: August 2021

Application of 16298-03-6, 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. 16298-03-6, name is Methyl 2-aminopyrazine-3-carboxylate, This compound has unique chemical properties. The synthetic route is as follows.

Example 3a: methyl 3-amino-6-iodopyrazine-2-carboxylate 1.5 equivalents of N-iodosuccinimide are added at room temperature to 5 g (32.7 mmol) of a methyl 3-aminopyrazine-2-carboxylate solution in 25 ml of dimethylformamide. The reaction medium is heated at 65 °C for 1 hour, added together with 0.5 equivalents of N-iodosuccinimide and maintained at 65°C for 24 hours. After returning to room temperature, the solvent is evaporated and then the product is extracted several times with dichloromethane. The organic phases are combined, washed with 10percent sodium bisulfite solution, dried on magnesium sulfate and concentrated to yield 8 g (88percent>) of methyl 3-amino-6-iodopyrazine-2-carboxylate in the form of a yellow solid. LCMS (EI, m/z): (M+l) 280 1H NMR: deltaEta ppm (400 MHz, DMSO): 8.50 (1H, s, CHarom), 7.50 (2H, bs, NH2), 3.20 (3H, s, CH3).

The chemical industry reduces the impact on the environment during synthesis Methyl 2-aminopyrazine-3-carboxylate. I believe this compound will play a more active role in future production and life.

Reference:
Patent; PIERRE FABRE MEDICAMENT; KRUCZYNSKI, Anna; CREANCIER, Laurent; KALOUN, El Bachir; BEDJEGUELAL, Karim; RABOT, Remi; WO2014/16434; (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. 24241-18-7, name is 2-Amino-3,5-dibromopyrazine, A new synthetic method of this compound is introduced below., Product Details of 24241-18-7

Step 3: 2-bromo-7-nitro-5H-pyrrolo[2,3-b]pyrazine[00199] 2-bromo-5H-pyrrolo[2,3-b]pyrazine (20 g, 101.0 mmol) was dissolved in ice-cold sulfuric acid (140.0 mL) , producing a bright orange solution, and concentrated nitric acid (12.73 g, 8.470 mL, 202.0 mmol) was added drop wise with stirring over 30 min keeping the temperature under 10 C (turning the solution to a clear red colour). The reaction was removed from the ice bath after 30 min and allowed to warm to ambient temperature and left to stir at ambient temperature for 1 hour. The reaction mixture was poured onto ice to obtain a yellow solid. The solid was filtered, washed with water to give 2-bromo-7-nitro-5H- pyrrolo[2,3-b]pyrazine the desired product as a yellow solid. (21.76 g, 88.7%). MS (ES+) 244.87.

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; VERTEX PHARMACEUTICALS INCORPORATED; MACCORMICK, Somhairle; STORCK, Pierre-henri; MORTIMORE, Michael, Paul; CHARRIER, Jean-damien; KNEGTEL, Ronald; YOUNG, Stephen, Clinton; PINDER, Joanne; DURRANT, Steven, John; WO2012/178123; (2012); 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. 4774-15-6, name is 2,6-Dimethoxypyrazine, A new synthetic method of this compound is introduced below., Quality Control of 2,6-Dimethoxypyrazine

General procedure: Representative procedure for the preparation of 1-phenoxycarbonyl-2-phenyl-3-methoxy-1,2-dihydropyrazine (3a). To a stirred solution of 2-methoxypyrazine (0.200 g, 1.816 mmol) inanhydrous THF (5 mL) was added phenylchloroformate (0.28 mL, 2.225 mmol) at 0 C andstirring was continued under nitrogen atmosphere until salt formation was completed (15 min, asdetermined by TLC on neutral alumina, EtOAc/hexanes 1:19). The reaction mixture was cooledto -41 C, a 1 M solution of phenylmagnesium bromide in THF (2.4 mL, 2.4 mmol) was addedand the mixture stirred until reaction completion (40 min, as determined by TLC on neutral SiO2,EtOAc/hexanes 1:9), and then quenched with 2 mL of aqueous 20% NH4OH/NH4Cl 1:1 (w/w).The mixture was extracted with dichloromethane (2 × 15 mL), dried over Na2SO4, andconcentrated in vacuo. Purification of the crude mixture by flash silica gel columnchromatography (0-15% EtOAc/hexanes) afforded 3a (0.488 g, 87%) as a white solid (3:2mixture of rotamers): mp: 81-82 C; 1H NMR (CDCl3, 500 MHz) delta 7.49-7.27 (m, 7H), 7.20 (t, J= 7.5 Hz, 1H), 7.12 (d, J = 8.0 Hz, 1H), 6.99 (d, J = 7.5 Hz, 1H), 6.67 and 6.63 (2d due torotamers, J = 5.5 Hz, 1H), 6.16 and 6.14 (2d due to rotamers, J = 5.0 Hz, 1H), 5.89 and 5.87 (2sdue to rotamers, 1H), 3.84 and 3.83 (2s due to rotamers, 3H); 13C NMR (CDCl3, 125 MHz) delta160.2, 160.0, 151.6, 151.5, 150.7, 150.4, 136.8, 135.9, 129.3, 128.8, 128.7, 128.6, 127.2, 126.6,125.9, 125.8, 121.3, 118.2, 118.1, 112.5, 111.8, 56.0, 54.6, 54.0, 53.9; HRMS (ESI) m/z calcdfor C18H17N2O3 [M + H]+ 309.12337, found 309.123554

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; St Hilaire, Valentine R.; Hopkins, William E.; Miller, Yenteeo S.; Dandepally, Srinivasa R.; Williams, Alfred L.; Beilstein Journal of Organic Chemistry; vol. 15; (2019); p. 72 – 78;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 98-97-5, The chemical industry reduces the impact on the environment during synthesis 98-97-5, name is Pyrazine-2-carboxylic acid, I believe this compound will play a more active role in future production and life.

To a solution of pyrazine-2-carboxylic acid (1.36 g, 10.9 mmol, 1 eq.) in SOCl2 (20 mL) was added DMF (2 drops). The mixture was stirred at 60 C. for 20 min. The volatiles were removed in vacuo to give crude pyrazine-2-carbonyl chloride, which was used in the next step directly. To a suspension of 2-amino-5-nitrobenzoic acid (2.00 g, 10.9 mmol, 1.0 eq.) in THF (50 mL) was added Et3N (1.09 g) and pyrazine-2-carbonyl chloride in anhydrous THF (50 mL) dropwise. The resulting mixture was stirred at room temperature for 18 h. After the reaction was completed, the volatiles were removed. The residue was suspended in H2O (10 mL) and the pH was adjusted to 5 by slow addition of 2N HCl in water. The resulting solid was collected and dried in vacuo to give 3.12 g of 5-nitro-2-(pyrazine-2-carboxamido)benzoic acid as a brown solid (99%). LCMS m/z=289.0 (M+1) (Method B) (retention time=1.24 min)

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, Pyrazine-2-carboxylic acid, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; Suzuki, Masaki; Kondo, Kazumi; Kurimura, Muneaki; Valluru, Krishna Reddy; Takahashi, Akira; Kuroda, Takeshi; Takahashi, Haruka; Fukushima, Tae; Miyamura, Shin; Ghosh, Indranath; Dogra, Abhishek; Harriman, Geraldine; Elder, Amy; Shimizu, Satoshi; Hodgetts, Kevin J.; Newcom, Jason S.; US2015/307477; (2015); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 109838-85-9, 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. 109838-85-9, name is (R)-2-Isopropyl-3,6-dimethoxy-2,5-dihydropyrazine belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below.

Step A – Preparation of Compound Int- 13cA 5 L- 3 necked round bottomed flask, equipped with a mechanical stirrer, temperature probe, addition funnel and N2 inlet, was charged with the Schollkopf chiral auxiliary-(Int-13a, 200 g, 1.09 mol, 1.0 eq), bis(chloromethyl) dimethylsilane (Int-13b, 256 g, 1.63 mol, 1.5 eq), and THF (2 L, Aldrich anhydrous). The flask was cooled in a dry ice/ 2- propanol bath until the internal temperature reached -75 °C. n-Butyllithium (Aldrich 2.5 M in hexanes , 478 mL, 1.19 mol, 1.09 eq) was added via a dropping funnel over 1 hour while maintaining the internal reaction temperature between -67 °C and -76 °C. The resulting orange-red solution was allowed to gradually warm to room temperature for about 15 hours. The reaction mixture was then re-cooled to 0 °C and quenched with 500 mL of water.Diethyl ether (2L) was added and the layers were separated. The aqueous layer was extracted with 1 L of diethyl ether. The combined organic layers was washed with water and brine, dried with MgS04, filtered, and concentrated in vacuo to dryness, giving 480 g of orange oil. This material was left in vacuo for about 15 hours to provide 420 g of oil. The crude product was split into two batches and purified via silica gel chromatography on a 1.6 kg flash column. The column was eluted with gradient of 0-4percent Et20 in hexanes. The product fractions were concentrated in vacuo at a bath temperature at or below 40 °C giving 190 grams of Int-13c-(60percentyield).

The synthetic route of (R)-2-Isopropyl-3,6-dimethoxy-2,5-dihydropyrazine has been constantly updated, and we look forward to future research findings.

Reference:
Patent; MERCK SHARP & DOHME CORP.; DWYER, Michael P; KEERTIKAR, Kartik M; COBURN, Craig A; WU, Hao; HU, Bin; ZHONG, Bin; ZHANG, Chengren; DAN, Zhigang; TONG, Ling; YU, Wensheng; WO2012/41227; (2012); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 1379338-74-5, 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. 1379338-74-5, name is 5,7-Dichloropyrido[3,4-b]pyrazine belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below.

A) (S)-terf-butyl 3-((7-chloropyrido[4,3-ib]pyrazi n-5-ylami no)methyl)piperidi ne- 1 -carboxylate.A solution of (S)-teri-butyl 3-(aminomethyl)piperidine-1 -carboxylate (100 mg, 0.5 mmol), 5,7-dichloropyrido[4,3-£>]pyrazine (100 mg, 0.5 mmol) and DIPEA (77 mg, 0.6 mmol) in THF (5 mL) was stirred at room temperature for 4 hours. The volatiles were removed under reduced pressure, and the residue was treated with ethyl acetate, with brine, and concentrated to give the crude title compound.

The synthetic route of 5,7-Dichloropyrido[3,4-b]pyrazine has been constantly updated, and we look forward to future research findings.

Reference:
Patent; HUTCHISON MEDIPHARMA LIMITED; SU, Wei-Guo; DENG, Wei; JI, Jianguo; WO2012/167733; (2012); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 14508-49-7,Some common heterocyclic compound, 14508-49-7, name is 2-Chloropyrazine, molecular formula is C4H3ClN2, 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 2-chloropyrazine (4.00 g) and hydrazine hydrate was heated at 110 C. for 1 h, and then cooled to room temperature. The mixture was filtered to give the title compound as a solid (2.30 g, 60.00%). The compound was characterized by the following spectroscopic data: MS (ESI, pos. ion) m/z: 111.0 (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 2-Chloropyrazine, its application will become more common.

Reference:
Patent; SUNSHINE LAKE PHARMA CO., LTD.; Zhang, Jiancun; Zhang, Yingjun; Zhang, Weihong; Liu, Bing; Zhang, Jiquan; Liu, Jinlei; Zhang, Lu; US2014/228361; (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. 56423-63-3, name is 2-Bromopyrazine, A new synthetic method of this compound is introduced below., Quality Control of 2-Bromopyrazine

A solution of 1-(4-(3,4-dichlorophenyl)-5-(isopropylthio)thiazol-2-yl)-5- (methoxycarbonyl)-3-methyl-1H-pyrazol-4-ylboronic acid (50 mg, 0.10 mmol), 2- bromopyrazine (20 mg, 0.12 mmol), Pd(PPh3)4 (12 mg, 0.10 mmol), Na2CO3 (54 mg, 0.51 mmol) in degassed 1,4-dioxane and H2O (4:1, 2.1 mL) was heated at 85 C for 18 hours. LiOH (12.4 mg, 0.52 mmol) was added and the reaction was heated at 90 oC under microwave radiation for 15 minutes.1 N HCl (1 mL) was added, followed by water (5 mL) and the mixture was extracted with EtOAc (3x5mL). The combined organic layers were dried with sodium sulfate, filtered and evaporated under reduced pressure. The crude product was purified by reverse chromatography on C-18 column using a solution of MeCN in water (containing 10 mM of NH4CO2H) (30 to 70%). The product was lyophylised and afforded the title compound (10 mg, 0.020 mmol, 20%) as a pale yellow solid. 1H NMR (500 MHz, DMSO) delta 8.97 (s, 1H), 8.71 (s, 1H), 8.58 (s, 1H), 8.23 (d, J = 1.9 Hz, 1H), 8.04 (dd, J = 8.4, 2.0 Hz, 1H), 7.76 (d, J = 8.5 Hz, 1H), 3.36 (hept, J = 6.7 Hz, 1H), 2.47 (s, 3H), 1.24 (d, J = 6.7 Hz, 6H); MS (m/z): 505.9 [M+H]+.

The synthetic route of 56423-63-3 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; BANTAM PHARMACEUTICAL, LLC; SIDDIQUI, M., Arshad; CIBLAT, Stephane; DERY, Martin; CONSTANTINEAU-FORGET, Lea; GRAND-MAITRE, Chantal; GUO, Xiangyu; SRIVASTAVA, Sanjay; SHIPPS, Gerald, W.; COOPER, Alan, B.; BRUNEAU-LATOUR, Nicolas; LY, Vu, Linh; (314 pag.)WO2016/196644; (2016); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 1174321-06-2, name is 5-(Difluoromethyl)pyrazine-2-carboxylic acid, 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 1174321-06-2, Safety of 5-(Difluoromethyl)pyrazine-2-carboxylic acid

Step 9: tert- Butyl ((4aS,5SJaS)-7a-(5-(5-(difluoromethyl)pyrazine-2-carboxamido)-2- fluorophenyl)-3-methyl-4-oxo-5-(trifluoromethyl)-3,4,4a,5J,7a-hexahydrofuror3,4- dlpyrimidin-2-yl)carbamate N- Ethyl-N-(propan-2-yl)propan-2- amine (300 muL, 1.7 mmol) was added to a stirred mixture of tert-butyl ((4aS,5S,7aS)-7a-(5-amino-2-fluorophenyl)-3-methyl-4-oxo-5- (trifluoromethyl)-3,4,4a,5,7,7a-hexahydrofuro[3,4-d]pyrimidin-2-yl)carbamate amine (150 mg, 0.34 mmol), 5-(difluoromethyl)pyrazine-2-carboxylic acid (90 mg, 0.50 mmol) and (lH-benzotriazol-l-yloxy)(tripyrrolidin-l-yl)phosphoniumhexafluorophosphate (265 mg, 0.50 mmol) in dry DCM (2 mL) at RT under nitrogen. The reaction was stirred at this temperature for 16 h, then partitioned between DCM and NaHCO3 (aq). The aqueous layer was extracted with DCM (x2). The combined extracts were dried by passing through a hydrophobic frit and then evaporated. The residue was purified by column chromatography (normal phase, 25 g, Biotage SNAP cartridge KP-SiI, 25mL per min, gradient 5% to 30% EtOAc in n-hexane) to give the title compound (92 mg, light yellow solid). 1H NMR (400 MHz, CDCl3) delta ppm 1.58 (s, 9H) 3.36 (s, 3H) 4.06 (d, J=7.83 Hz, IH) 4.40 (d, J=9.85 Hz, IH) 4.50 (dd, J=9.73, 2.91 Hz, IH) 4.57 – 4.65 (m, IH) 6.81 (t, J=54.60 Hz, IH) 7.22 (dd, J=10.86, 9.09 Hz, IH) 7.74 (dd, J=6.69, 2.65 Hz, IH) 7.84 (ddd, J=8.84, 4.17, 2.65 Hz, IH) 8.93 (s, IH) 9.52 (s, IH) 9.65 (s, IH) 10.64 (s, IH)

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; EISAI R&D MANAGEMENT CO., LTD; CASTRO PINEIRO, Jose, Luis; HALL, Adrian; MADIN, Andrew; VO, Ngoc-Tri; WO2011/9897; (2011); 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. 27398-39-6, name is 3-Chloropyrazine-2-carboxylic acid, A new synthetic method of this compound is introduced below., Recommanded Product: 27398-39-6

To a suspension of 3-chloropyrazine-2-carboxylic acid (5.46 g) in THF (100 mL) was added CDI (6.14 g) at room temperature, and the mixture was stirred at room temperature for 30 min and heated to 50 °C. After stirring at 50 °C for 1 h, the mixture was cooled to room temperature. To the mixture were added N, O-dimethylhydroxylamine hydrochloride (5.04 g) and DIPEA (9.02 mL) at room temperature, and the mixture was stirred at room temperature overnight. The mixture was concentrated under reduced pressure. The residue was purified by silica gel column chromatography (AcOEt/hexane) to give the title compound (3.05 g) .MS (API+) : [M+H]+ 202.1.H NMR (300 MHz, CDC13) delta 3.43 (3H, s) , 3.58 (3H, s), 8.44 (1H, d, J = 2.3 Hz>, 8.52 (1H, d, J = ‘2.3 Hz).

The synthetic route of 27398-39-6 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; TAKEDA PHARMACEUTICAL COMPANY LIMITED; RAKER, Joseph; TANIGUCHI, Takahiko; YOSHIKAWA, Masato; HASUI, Tomoaki; KUNITOMO, Jun; WO2012/18909; (2012); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem