Category: Pyrazines

Synthetic Route of 98-97-5,Some common heterocyclic compound, 98-97-5, name is Pyrazine-2-carboxylic acid, molecular formula is C5H4N2O2, 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.

Pyrazinecarboxylic acid (2.72 g, 21.9 mmol) was added to a solution of L- cyclohexylglycine methyl ester (4.13 g, 19.9 mmol) in CH2CI2 (100 ml) at room temperature under N2, forming a white suspension. Triethylamine (6.33 ml, 4.62 g, 45.8 mmol) was added, followed by benzotriazol-l-yloxy-tris-(dimethylamino)- phosphonium hexafluorophosphate (BOP; 9.69 g, 21.9 mmol), which turned the reaction mixture from purple to an orange solution. After two days of stirring at room temperature the reaction mixture was washed two times with 50 ml saturated Na2CC>3, followed by the washing of the aqueous layers with CH2CI2 (2 chi 50 ml). The organic layers were collected and dried with MgSC , followed by concentration in vacuo. Purification by silica gel flash chromatography (c-Hex:EtOAc = 2: 1 with 0.5% triethylamine) afforded 9 (5.28 g, 19.03 mmol, 96%) as a yellow oil that solidified upon standing to give a white solid.[a f = +42.5 (c= 1.13, CHC13); *H NMR (250.13 MHz, CDCI3) delta = 9.39 (d, J= 1.25 Hz, 1H), 8.76 (d, J = 2.5 Hz, 1H), 8.57 (t, J = 1.5 Hz, 1H), 8.25 (d, J = 8.8 Hz, 1H), 4.74 (dd, J= 5.5, 9.3 Hz, 1H), 3.78 (s, 3H), 1.96 (m, 1H), 1.77 (m, 5H), 1.24 (m, 5H); 13C NMR (62.90 MHz, CDCI3): delta= 172.0 (C), 162.8 (C), 147.4 (CH), 144.5 (CH), 144.1 (C), 142.7(CH), 57.0 (CH), 52.3 (CH3), 41.2 (CH), 29.7 (CH2), 28.4 (CH2), 26.0 (CH2); IR (neat): v^cm ) = 3374 (m), 2920 (s), 2845 (w), 1740 (s), 1665 (s); HRMS (ESI, 4500 V): m/z calcd. for Ci4Hi9N303Na+ ([M + Na]+) 300.1319, found 300.1319.

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

Reference:
Patent; VERENIGING VOOR CHRISTELIJK HOGER ONDERWIJS, WETENSCHAPPELIJK ONDERZOEK EN PATIENTENZORG; RUIJTER, Eelco; ORRU, Romano; ZNABET, Anass; POLAK, Marloes; TURNER, Nicholas; WO2011/103932; (2011); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 21279-64-1, 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. 21279-64-1 name is 5-Chloropyrazine-2-carboxamide, 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.

5-[18F]F-PZA was synthesized via a halogen exchange reaction, similar to the method used tosynthesize 5-F-PZA (Fig 2). 2960 MBq (80 mCi) of aqueous [18F]fluoride in ddH2O was purchasedfrom PETNET Solutions Inc. The [18F]fluoride was placed in a vial containing Kryptofix2.2.2 (5 mg, 13 mumol) and potassium carbonate (1 mg, 7 mumol) and the solution was thendried by azeotropic distillation. The solid residue was then re-solubilized with 0.2±0.3 mL ofacetonitrile containing 1±2 mg 5-chloropyrazinamide (5-Cl-PZA). The reaction mixture washeated in a securely capped 2 mL reaction vial at 105C for 8 min, and subsequently quenchedwith 0.8 mL water. The reaction mixture was filtered through a vented 0.22 um Millipore filterusing a 1 mL syringe and then purified by HPLC with an isocratic mobile phase of 8% acetonitrile/92% 0.02Maqueous ammonium acetate with 5% acetic acid (Phenomenex Luna PFP,250 × 10, 5 mum, 4 mL/min). The radioactive product eluted at the same retention time as the5-F-PZA standard (10 to 12 min). The solvent was removed by rotary evaporation. The residuewas re-solubilized in sterile phosphate buffered saline and the pH of the solution was adjustedto 7.4 by the addition of 2M NaOH. The solution was filtered through an Acrodisc 13 mmsyringe filter equipped with a 0.2 mum Supor membrane (Pall Corporation) into a sterile vial.Radiochemical purity was determined by reverse-phase analytical HPLC (Phenomenex PFP,250 × 4.6, 5 mum, 1 mL/min, 8% acetonitrile/92% 0.02Maqueous ammonium acetate with 5%acetic acid mobile phase).

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

Reference:
Article; Zhang, Zhuo; Ordonez, Alvaro A.; Smith-Jones, Peter; Wang, Hui; Gogarty, Kayla R.; Daryaee, Fereidoon; Bambarger, Lauren E.; Chang, Yong S.; Jain, Sanjay K.; Tonge, Peter J.; PLoS ONE; vol. 12; 2; (2017);,
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. 6705-33-5, name is Pyrazin-2-ylmethanol, A new synthetic method of this compound is introduced below., SDS of cas: 6705-33-5

General procedure: Freshly prepared Ag2O (2.20 mmol) was added at room temperature to a solution of pyridin-2-ylmethanol (1.00 mmol) and 2-iodopropane (2.20 mmol) in 1,4-dioxane (10 mL) and stirred for 24 h. The reaction mixture was filtered through a Celite bed and washed with ethyl acetate. Filtrate was concentrated under vacuum.The resulting material was purified by flash chromatography on a Biotage instrumentusing 4-g flash cartridge and eluted with 12-15% ethyl acetate in hexane to give isopropyl picolinate (2) (65% yield).

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; Patil, Vikas S.; Reddy, M. Rajendar; Pal, Shyam Sundar; Sharma, Somesh; Reddy, L. Krishnakanth; Synthetic Communications; vol. 44; 14; (2014); p. 2121 – 2127;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 274-79-3, name is Imidazo[1,2-a]pyrazine, 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 274-79-3, Recommanded Product: 274-79-3

Step 1 The indole obtained [1,2-A] pyrazine (10g, 0.08mmol) was dissolved in 100mL of ethylene glycol monomethyl ether, was added 5% palladium on carbon (2G), quickly replaced with hydrogen three times, at room temperature (20-25 ) The reaction was stirred, TLC detection reaction process, the reaction is complete after 30 hours, suction filtered through celite pad, and the filtrate was concentrated by rotary evaporation and purified by column chromatography by chromatography to give 5,6,7,8- hydrogen-imidazo [1,2-A] pyrazine 7g, the the yield of about 68%

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; shanghai bide pharmatech co. ltd; LI, JINFEI; HUANG, LIANGFU; LI, XINLING; WANG, MINGXIA; (5 pag.)CN103864799; (2016); B;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 89123-58-0,Some common heterocyclic compound, 89123-58-0, name is 5-Bromopyrazine-2,3-diamine, molecular formula is C4H5BrN4, 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 solution of 50 mg (0.27 mmol) of 5-bromopyrazine-2,3-diamine in 2 mL of a 10: 1 solution of methanol/acetic acid was added 0.046 mL (0.40 mmol) of glyoxal solution (40 wt. % in water) and the resulting solution was stirred at 50 0C for 4 h. The reaction mixture was cooled to ambient temperature, diluted with 10 mL of ethyl acetate and washed with saturated aqueous sodium bicarbonate solution, and saturated aqueous brine (5 mL each). The organic phase was then dried over anhydrous sodium sulfate, filtered, and evaporated in vacuo to yield the title compound as a tan crystalline solid which was used without further purification. LC/MS 211.1, 213.1 (M+ 1, M+3).

The synthetic route of 89123-58-0 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; MERCK & CO., INC.; WO2006/39325; (2006); A2;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 4774-14-5, The chemical industry reduces the impact on the environment during synthesis 4774-14-5, name is 2,6-Dichloropyrazine, I believe this compound will play a more active role in future production and life.

Step 1: N-Benzyl-6-Chloro-2-Pyrazinamine. A mixture of 2,6-dichloropyrazine (1.31 g, 8.8 mmol), benzylamine (1.15 g, 10.7 mmol) and K2CO3 (1.65 g, 11.9 mmol) in acetonitrile (6 mL) was heated at 85 C. for 13 h in a sealed pyrex flask. The reaction mixture was diluted with dichloromethane, filtered and concentrated in vacuo. The yellow solid residue was dissolved in a small volume of methanol and purified by silica gel chromatography (18*4 cm) using CHCl3/MeOH (98:2) as eluent. A second purification (SiO2;16*4 cm) using CHCl3 as eluent furnished 1.55 g (81%) of the title compound as a light yellow solid. HRMS m/z calcd for C11H10ClN3 (M)+219.0563, found 219.0568. Anal. (C11H10ClN3) C, H, N.

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, 2,6-Dichloropyrazine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; Nilsson, Bjorn M.; US2002/147200; (2002); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

13924-95-3, name is Methyl 5-hydroxypyrazine-2-carboxylate, 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. Formula: C6H6N2O3

(62b) Methyl 5-Chloropyrazine-2-carboxylate Methyl 5-hydroxypyrazine-2-carboxylate (673 mg, 4.37 mmol) synthesised in Example (62a) was dissolved in phosphorous oxytrichloride (6.1 mL), and a few drops of N,N-dimethylformamide were added, followed by heating to reflux for 2 hours under nitrogen atmosphere. The reaction solution was poured into ice water, and extraction was carried out three times with chloroform (30 mL). The organic layer was washed with saturated aqueous sodium hydrogencarbonate solution and saturated brine (100 mL each), and subsequently dried over sodium sulfate. The solvent was distilled off under reduced pressure to afford the desired compound (611 mg, yield 81%) as a gray solid. 1H-NMR (CDCl3, 400 MHz): delta 4.05 (3H, s), 8.71 (1H, d, J=1.6 Hz), 9.10 (1H, d, J=1.2 Hz).

The synthetic route of 13924-95-3 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Daiichi Sankyo Company, Limited; EP2239253; (2010); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 54608-52-5,Some common heterocyclic compound, 54608-52-5, name is 2-Hydrazinopyrazine, molecular formula is C4H6N4, 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 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.

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

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

Some common heterocyclic compound, 486424-37-7, name is 3-Amino-6-bromopyrazine-2-carboxylic acid, molecular formula is C5H4BrN3O2, 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. HPLC of Formula: C5H4BrN3O2

A solution of 3-amino-6-bromo-pyrazine-2-carboxylic acid (0.62 g, 2.8 mmol), HATU (1.3 g, 3.4 mmol) and di-isopropylethylamine (1.72 ml, 3.5 mmol) in DMF (20 ml) is stirred at room temperature for 5 minutes. N-Methoxy-N-methylamine hydrochloride (0.33 g, 3.4 mmol) is added and the reaction is stirred at room temperature for 2 hours. The solvent is concentrated in vacuo and the residue dissolved in EtOAc (30 ml), and washed with sat. aq. NaHCO3 (20 ml), 0.1N HCl (20 ml), dried (MgSO4) and concentrated in vacuo to yield a brown oil. Purification by flash chromatography (SiO2, 30% EtOAc in iso-hexane) yields 3-amino-6-bromo-pyrazine-2-carboxylic acid methoxy-methyl-amide as a yellow solid [M+H]+ 261.

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 486424-37-7, its application will become more common.

Reference:
Patent; BRUCE, Ian; BUDD, Emma; EDWARDS, Lee; HOWSHAM, Catherine; US2009/239847; (2009); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 32974-92-8, 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. 32974-92-8, name is 1-(3-Ethylpyrazin-2-yl)ethanone, This compound has unique chemical properties. The synthetic route is as follows.

Example 1862-(N-isopropylbenzyl)aminoethyl-2-(3-ethyl)-pyrazylketone 8656 2-acetyl-3-ethylpyrazine (151 mg), benzylisopropylamine (149 mg), and paraformaldehyde (40 mg) were reacted in dioxane (0.2 ml) at 130 C. for 2 hours.NMR (CDCl3) 1.1-1.2 (m, 6H), 2.7 (m, 1H), 3.1 (m, 4H), 3.7 (m, 2H), 7-7.2 (m, 1H)TG 29 (3 mumol) 16 (10 mumol) 14 (30 mumol)SOCE 0 (10 mumol) 0 (30 mumol) 10 (100 mumol)IICR 70 (10 mumol) 90 (30 mumol) 100 (100 mumol)

The chemical industry reduces the impact on the environment during synthesis 1-(3-Ethylpyrazin-2-yl)ethanone. I believe this compound will play a more active role in future production and life.

Reference:
Patent; Japan Science and Technology Agency; US2012/277423; (2012); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem