Month: September 2021

Application of 89123-58-0, The chemical industry reduces the impact on the environment during synthesis 89123-58-0, name is 5-Bromopyrazine-2,3-diamine, I believe this compound will play a more active role in future production and life.

Oxalyl chloride (3ml) was added to a solution of 5-({5-chloro-2-[(2-methylpropyl)oxy]- phenyl}methyl)-2-furancarboxylic acid (3.09g, lOmmol) and one drop of DMF in dichloromethane (30ml) and left at room temperature for one hour. The resulting solution was evaporated to dryness, azeotroped with toluene and the residue dissolved in dichloromethane (15ml) and added dropwise to a stirred solution of 2,3-diamino-5- bromopyrazine (2.08g, 11mmol) and 4-dimethyaminopyridine (100mg, 0.82mmol) in pyridine (20ml) and stirred for one hour. The solution was evaporated and the residue dissolved in ether/water. The organic phase was dried with magnesium sulphate, evaporated and chromatographed on silica gel eluting with ethyl acetate/hexane (15:85) to give 3.35g of white solid which was dissolved in acetic acid (40ml) and stirred and refluxed for 5 days. The resulting solution was evaporated, dissolved in ethyl acetate and washed with 2M sodium hydroxide solution. The organic phase was dried with magnesium sulphate, evaporated and purified by flash chromatography on silica eluting with ethyl acetate/hexane (1 :3) to give a pale yellow solid. A sample was dissolved in methanol/dichloromethane and hydrogen chloride in ether (1ml) was added. The solvent was evaporated and the residue triturated with ether and filtered off to give the title compound as a solid. LC/MS: Rt=3.67, [MH]+ 463.11 , 464.16.

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, 5-Bromopyrazine-2,3-diamine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; GLAXO GROUP LIMITED; WO2006/114272; (2006); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 5049-61-6, These common heterocyclic compound, 5049-61-6, name is Pyrazin-2-amine, 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 2-aminopyrazine (i) (2 g, 21.02 mmol) in dry DCM (10 ml) was added NBS (3.78 g, 21.23 mmol) portion-wise under cold condition and the resulting mixture was allowed to stir at RT for 6h. 5 ml of water was added and the layers were separated. Aqueous layer was extracted with DCM (10 ml X 2). Combined organic layers were washed with Brine solution (5 ml), dried over anhydrous Na2S04 and concentrated under vacuum. Crude material was purified by column chromatography over silica gel 230-400 mesh by using 18% of ethyl acetate in petroleum ether as an eluent to afford compound (ii) (1.98 g, 54.42%) as white solid.

The synthetic route of 5049-61-6 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; UNIVERSITY OF CAPE TOWN; MMV MEDICINES FOR MALARIA VENTURE; YOUNIS, Yassir; CHIBALE, Kelly; WITTY, Michael, John; WATERSON, David; WO2013/121387; (2013); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 486424-37-7,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.

CDI (2.23 g, 13.8 mmol) was added to a suspension of commercial 3-amino-6- bromopyrazine-2-carboxylic acid (2.00 g, 9.17 mmol) in DMF (20 ml). The reaction was stirred at RT for 16 h. The reaction mixture was cooled (0 C) then diluted with water (20 ml). The solid was collected by filtration then washed with the minimum volume of water and cooled (0 C) MeCN then dried under vacuum to afford the product as a yellow solid (2.23 g, 86%). 1H NMR (250 MHz, DMSO-cfe) delta 8.55 (s, 2H), 7.96 – 7.82 (m, 3H), 7.15 – 7.07 (dm, 1 H). LC/MS (System A, MeOH quench): m/z (ESI+) = 232 [Methyl ester M(79Br)H+], 234 [Methyl ester M(81Br)H+]), Rt = 0.87 min, UV purity = 95%.

The synthetic route of 486424-37-7 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; ENTERPRISE THERAPEUTICS LIMITED; MCCARTHY, Clive; HARGRAVE, Jonathan David; HAY, Duncan Alexander; SCHOFIELD, Thomas Beauregard; WENT, Naomi; (111 pag.)WO2017/221008; (2017); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 88625-24-5, 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. 88625-24-5 name is 5-Chloropyrazine-2-carbaldehyde, 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.

2) N,N-dimethylformamide (10 mL) was added to 5-chloropyrazine-2-carbaldehyde (500 mg), methyl 2,2-dimethyl-3-{[4-methyl-5-(4,4,5,5-tetramethyl-l,3,2-dioxaborolan- 2-yl)pyridin-2-yl]oxy}propanoate (1410 mg) and 2N aqueous sodium carbonate solution (5.26 mL), and after replacing the atmosphere with nitrogen, palladium chloride (dppf) methylene chloride complex (143 mg) was added to the mixture and the resulting mixture was stirred at 65C for 2 hours. To the reaction mixture were added ethyl acetate and water, and the liquids were separated. After filtration with Celite, the organic layer was separated, washed with water and then with a saturated brine, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The obtained residue was purified by silica gel column chromatography (n-hexane: ethyl acetate=100:0 to 70:30) to obtain methyl 3-{[5-(5-formylpyrazin-2-yl)-4-methylpyridin- 2-yl]oxy}-2,2-dimethylpropanoate (855 mg). MS (m/z): 330 [M+H]+

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

Reference:
Patent; MITSUBISHI TANABE PHARMA CORPORATION; SAKURAI, Osamu; SARUTA, Kunio; HAYASHI, Norimitsu; GOI, Takashi; MOROKUMA, Kenji; TSUJISHIMA, Hidekazu; SAWAMOTO, Hiroaki; SHITAMA, Hiroaki; IMASHIRO, Ritsuo; WO2012/81736; (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. 33332-25-1, name is Methyl 5-chloropyrazine-2-carboxylate, A new synthetic method of this compound is introduced below., category: Pyrazines

Diisobutylaluminium hydride (1.0 M in toluene; 6.4 mL, 6.40 mmol) was added dropwise to a cooled solution of methyl 5-chloropyrazine-2-carboxylate (690 mg, 4.00 mmol) in THF (13.6 mL) at -55 C. The reaction was stirred under these conditions for 1 hour and then quenched by addition of saturated aqueous NH4C1 (25 mL) and EtOAc (25 mL). An emulsion formed and 2N aqueous HC1 was added to clear the emulsion (5 mL). The layers were separated, and the aqueous layer was extracted with EtOAc. The organic layerwas washed with saturated aqueous sodium chloride, dried over magnesium sulfate and concentrated under reduced pressure. The resulting residue was purified by flash silica chromatography, elution gradient 0 to 50% EtOAc in heptane. Product fractions were evaporated to dryness to afford 5-chloropyrazine-2-carbaldehyde (385 mg, 68%) as a beige solid. ?H NMR (500 MHz, CDC13, 27 C) 8.75 (1H, d), 8.96 (1H, d), 10.15 (1H, d).

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; ASTRAZENECA AB; SCOTT, James, Stewart; MOSS, Thomas, Andrew; YANG, Bin; VARNES, Jeffrey, Gilbert; O’DONOVAN, Daniel, Hillebrand; NISSINK, Johannes, Wilhelmus, Maria; HUGHES, Samantha, Jayne; BARLAAM, Bernard, Christophe; WU, Dedong; BROO, Dan, Anders; (224 pag.)WO2018/19793; (2018); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 4774-14-5, name is 2,6-Dichloropyrazine, 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 4774-14-5, Formula: C4H2Cl2N2

A solution of compound 8 (450.0 g, 3.02 mol) in cone. aq. NH3 (3.0 L) was stirred at 135°C overnight in a 10 L sealed pressure vessel. TLC and LC/MS showed complete conversion of the starting material. The reaction mixture was cooled to room temperature and filtered to afford a white solid. The solid was washed with water (200 mL x 3), and then dried to afford compound 9 (312 g, 80percent yield) as a solid. 1HNMR (400 MHz, DMSO- 6): delta 7.82 (s, 1 H), 7.12 (s, 1 H), 6.93 (s, 2H). MS Calcd.: 129 MS Found: 130 ([M+H]+).

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; IMARA, INC.; H. LUNDBECK A/S; SVENSTRUP, Niels; PARACHIKOVA, Anna I.; MCARTHUR, James; (133 pag.)WO2018/9424; (2018); 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 951626-95-2 as follows. 951626-95-2

To the solution of piperidine (25 mg, 0.29 mmol) in dry THF (5 mL) was added trimethylaluminium (0.14mL, 0.29 mmol) drop wise at -10C under nitrogen over a period of 10 min. This solution was allowed to stir at room temperature for 45 minutes. Further the reaction mixture was re-cooled to -10C and thereto was added a solution of compound 5a (50 mg, 0.22 mmol) in THF (2.5 mL) drop wise. The resulting reaction mixture was stirred at room temperature initially then refluxed for 18 h. Reaction mixture was cooled to room temperature and quenched with iso-propanol (IPA) followed by methanol and then with saturated Na2SO4 solution. The reaction mixture was filtered and the filtrate was evaporated to dryness. The crude material was purified by column chromatography on silica gel (100-200 mesh) using MeOH in DCM to give desired compound 6a (50 mg, 85%). MS (ES+) m/z: 249. 1H NMR (400 MHz, CDCl3) delta 7.13 (s, 1H), 6.14-6.28 (m, 1H), 4.43 (m, 2H), 3.77-3.85 (m, 2H), 3.68-3.74 (m, 4H), 1.51-1.76 (m, 6H)

According to the analysis of related databases, 951626-95-2, the application of this compound in the production field has become more and more popular.

Reference:
Article; Surase, Yogesh B.; Samby, Kirandeep; Amale, Sagar R.; Sood, Ruchi; Purnapatre, Kedar P.; Pareek, Pawan K.; Das, Biswajit; Nanda, Kamna; Kumar, Subodh; Verma, Ashwani K.; Bioorganic and Medicinal Chemistry Letters; vol. 27; 15; (2017); p. 3454 – 3459;,
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. 100047-56-1, name is 5-Bromo-3-methylpyrazin-2-ol, A new synthetic method of this compound is introduced below., HPLC of Formula: C5H5BrN2O

(ls,4s)-4-(l-Methylpiperidin-4-yloxy)cyclohexanol (1.2 g, 5.63 mmol) was dissolved inTHF (10 mL), 5-bromo-3-methylpyrazin-2-ol (1.170 g, 6.19 mmol) and triphenylphosphine (1.771 g, 6.75 mmol) were added, then cooled down in an ice -water bath. DIAD (1.329 ml, 6.75 mmol) was added dropwise under N2. The reaction mixture was slowly warmed to room temperature, stirred overnight, and concentrated. The residue was purified by preparative HPLC (15-80% CH3CN/H20 with 0.1 % TFA over 30 min) and column chromatography (5% methanol/ethyl acetate containing 1 % Et3N) to give the title compound (525 mg, 1.366 mmol, 24.3% yield). Exact mass calculated for Ci7H26BrN302: 383.1 , found: LCMS m/z = 384.2[M+H]+; lU NMR (400 MHz, CDC13) 5 ppm 1.45-1.62 (m, 4H), 1.65-1.75 (m, 2H), 1.91-2.05 (m, 4H), 2.05-2.15 (m, 2H), 2.39 (s, 3H), 2.36-2.42 (m, 2H), 2.42 (d, J = 0.7 Hz, 3H), 2.78-2.85 (m, 2H), 3.46-3.54 (m, 2H), 4.95-5.02 (m, 1H), 7.98 (d, J = 0.6 Hz, 1H).

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; ARENA PHARMACEUTICALS, INC.; JONES, Robert M.; HAN, Sangdon; BUZARD, Daniel J.; LEHMANN, Juerg; NARAYANAN, Sanju; YUE, Dawei; WO2011/127051; (2011); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

3149-28-8, Adding some certain compound to certain chemical reactions, such as: 3149-28-8, name is 2-Methoxypyrazine, 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 3149-28-8.

To a solution of 2-methoxypyrazine (5.0g, 45.4mmol), in 40ml of anhydrous THF was added tributyltin hydride (15.0mL, 54.9mmol) and the resulting solution stirred under nitrogen at 0C. Cyclohexylcarbonyl chloride (8.0mL, 59.8mmol) was added over 10min and stirring continued until reaction completion in 20min as determined by TLC (neutral alumina, EtOAc/hexanes (1/19, v/v)). A 1M solution of HCl in methanol (20.0mL) was then added to the reaction mixture that was stirred under nitrogen at 0C until reaction completion in 30min as determined by TLC (SiO2, EtOAc/hexanes (2/3, v/v). The reaction mixture was quenched with 50mL of water, extracted with ethyl acetate (3×50mL), washed with saturated sodium bicarbonate (10mL), and then dried over anhydrous Na2SO4. Purification by silica gel flash column chromatography (100% hexanes: to remove tin by-products, followed by methanol / dichloromethane 2-5%) afforded 4-cyclohexanecarbonyl-1,2-dihydro-2-pyrazinone 3 (8.9g, 94%) as a pale yellow solid (mp 160-163C dec).

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 3149-28-8.

Reference:
Article; Williams, Alfred L.; St. Hilaire, Valentine R.; Tetrahedron; vol. 73; 48; (2017); p. 6712 – 6717;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 68774-77-6, name is 8-Chloro[1,2,4]triazolo[4,3-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 68774-77-6, HPLC of Formula: C5H3ClN4

A mixture of crude 4-methylbenzyl 4-(aminomethyl)-3,3-difluoropiperidine-1-carboxylate (600mg, 2.0 mmol), 8-chloro-[1,2,4]triazolo[4,3-a]pyrazine (360 mg, 2.0 mmol) and DIPEA (0.76 mL, 4.0 mmol) in butyl alcohol (10 mL) was heated at 130 C overnight. The mixture was allowed to cool to room temperature and concentrated under reduced pressure. The concentrate was purified by column chromatography over silica gel (100% ethyl acetate) to afford the title compound as a light gray powder (150 mg, 18%). MS (ESI) calcd for C20H22F2N602: 416.2; found: 417.3 [M+H]. 1H NMR (400MHz, CD3OD) 6 9.16 (s, 1H), 7.77 (d, J = 4.8 Hz, 1H), 7.29 (d, J = 4.8 Hz, 1H), 7.24 (d, J = 8.0 Hz, 2H), 7.17 (d, J = 8.0 Hz, 2H), 5.09 (s, 2H), 4.33 (br s, 1H), 4.19-4.15 (m, 1H), 4.05-3.95 (m, 1H), 3.72-3.58 (m, 1H), 3.25-2.90 (m, 2H), 2.67-2.51 (m,1H), 2.33 (s, 3H), 1.99-1.93 (m, 1H), 1.62-1.52 (m, 1H).

At the same time, in my other blogs, there are other synthetic methods of this type of compound, 8-Chloro[1,2,4]triazolo[4,3-a]pyrazine, and friends who are interested can also refer to it.

Reference:
Patent; RUGEN HOLDINGS (CAYMAN) LIMITED; SHAPIRO, Gideon; (246 pag.)WO2016/196513; (2016); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem