Pyrazines

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. 6966-01-4, name is Methyl 3-amino-6-bromopyrazine-2-carboxylate, A new synthetic method of this compound is introduced below., Application In Synthesis of Methyl 3-amino-6-bromopyrazine-2-carboxylate

Triisopropyl borate (2.7 mL, 11.6 mmol) was added to a solution of 1- [ (4- bromophenyl) SULFONYL]-4-METHYLPIPERAZINE in (1.24 g, 3.87 mmol; described: in Keasling, H. H. et el. J. Med. Chem. 1965, 8, 548-550) in anhydrous tetrahydrofuran (25 mL) at-78 C under an atmosphere of nitrogen, followed by dropwise addition of n-butyllithium (9.8 mL, 15.5 mmol). The resulting mixture was stirred at-78 C for 30 min, then allowed to warm to room temperature. HCl (3 M aq, 7.8 mL, 23.2 mmol) was added and the mixture was stirred at room temperature for 10 min. Sodium carbonate (4.1 g, 38.7 mmol) was added followed by the addition of methyl 3-amino-6-bromo-2-pyrazinecarboxylate (0.79 g, 3.4 mmol; described in: H. Ellingson, J. Amer. Chem. Soc. 1949,2798) and Pd (dppf) Cl2 (95 mg, 0.12 mmol). The resulting mixture was heated at 55 C overnight. Silica was added, the solvent was evaporated and the crude mixture was purified by column chromatography on silica using CHLOROFORM/METHANOL, (99: 1), as the eluent to give 0.923 g (69% yield) of the base as a yellow solid : 1HNMR (DMSO-D6) S 9.0 (s, 1 H), 8.22 (d, J = 7 Hz, 2 H), 7.80 (d, J = 7 HZ, 2 H), 7.62 (BR S, 2 H), 3.90 (s, 3 H) 2.91 (m, 4 H), 2.36 (m, 4 H), 2.12 (s, 3 H); 13CNMR (DMSO-D6) 8 166. 2,155. 1,145. 8,140. 33,127. 5,134. 0,128. 1, 125.7, 109.1, 53.5, 52.3, 45.7, 45.2 ; MS (ESP) M/Z 392 (M++1).

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; WO2004/55006; (2004); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 17890-77-6, These common heterocyclic compound, 17890-77-6, name is 3-Amino-6-bromopyrazine-2-carboxamide, 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.

In the equipped with magnetic stirring, of the reflux condensation tube (with drying tail pipe) of 250 ml in three-necked bottle, adding 13.1g (about 0.06 muM) 3 – amino pyrazine -2 – formamide, 60 ml of acetic anhydride, 60 ml ethyl trimethyl orthoformate, stirring under heating to reflux 4h, started when the reflux temperature 136 C, gradually reduced to 95 C, cooling to room temperature, filter, ice laundering, a brown solid.The crude isopropyl alcohol and water (1:1) about 300 ml of mixed the fluid is heavy crystallization, heating completely dissolved, add 2g activated carbon to decolorize 30min, heat filtering, washing. Cooling separating white solid. 60 C drying. Be 11.24g white powder that is 6 – bromo -4 (3H) dihydropteridinones. Yield: 82.5

The synthetic route of 17890-77-6 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Li Zhulai; (15 pag.)CN106699759; (2017); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 33332-25-1, These common heterocyclic compound, 33332-25-1, name is Methyl 5-chloropyrazine-2-carboxylate, 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.

Methyl 5-chloropyrazine-2-carboxylate (CAS no. 33332-25-1)(345.1 g) was dissolved in DMF (1.73 l). Lithium chloride (423.9 g) was added and the mixture heated to 140 C. over one hour. The mixture was evaporated, and the residue dissolved in water (3.4 l) by continued stirring. The solution was acidified by addition of 2N HCl (900 ml) and extracted into ethyl acetate (5×1.73 l). The combined organic extracts were washed with water (2×900 ml), brine (900 ml), dried (MgSO4), and evaporated to give the title compound (298.1 g). 1H NMR 6 (400.132 MHz, DMSO) 8.92 (d, 1H), 9.02 (d, 1H), 13.87 (s, 1H).

The synthetic route of 33332-25-1 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; AstraZeneca AB; US2008/153800; (2008); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 54608-52-5, name is 2-Hydrazinopyrazine, 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 54608-52-5, Recommanded Product: 54608-52-5

[00462] Step A: 5-amino-4-methyl-l-(pyrazin-2-yl)-lH-pyrazol-3(2H)-one: To a mixture of 2-hydrazinylpyrazine (0.551 g, 5.00 mmol) and ethyl 2-cyanopropanoate (0.669 g, 5.00 mmol) in abs. EtOH (10 mL) was added 3M NaOEt in EtOH (0.167 mL, 0.501 mmol) and the mixture was heated at reflux for 64 hours. The mixture was concentrated and the residual yellow-brown solid was treated with EtOAc (30 mL) and sonicated. The resulting tan suspension was stirred vigorously for 8 hours. The solid was collected via vacuum filtration, washed with EtOAc and dried in vacuum to afford the title compound as a light tan powder (682 mg, 71%). NMR (DMSO d6) delta 10.3 (br s, 1H), 8.82 (s, 1H), 8.30 (d, 2H), 6.55 (s, 2H), 1.71 (s, 3H).

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; ARRAY BIOPHARMA INC.; BRANDHUBER, Barbara, J.; JIANG, Yutong; KOLAKOWSKI, Gabrielle, R.; WINSKI, Shannon, L.; WO2014/78322; (2014); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 6966-01-4, name is Methyl 3-amino-6-bromopyrazine-2-carboxylate, 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 6966-01-4, Application In Synthesis of Methyl 3-amino-6-bromopyrazine-2-carboxylate

Palladium acetate (0.145 g) and [1,1′-bis(diphenylphosphino)ferrocene]dichloropalladium complex with DCM (0.702 g) were dissolved in DMF (65 ml) and heated to 50 C for 15 minutes. After cooling to room temperature 3-amino-6-bromo-pyrazine-2-carboxylic acid methyl ester (5.0 g), 4-fluoro-phenyl boronic acid (3.82 g) and triethylamine (4.5 ml ) were added and the mixture heated to 90 C for 20 hours with stirring. The solvent was evaporated and the residue dissolved in DCM. The organic phase was washed with dilute ammonium hydroxide solution and water. After drying with sodium sulphate and filtration the solvent was evaporated and the residue purified by column chromatography on silica gel eluting with hexane: ethyl acetate, 3: 1 to give 3-amino-6-(4-fluorophenyl)-pyrazine-2- carboxylic acid methyl ester (0.670 g). ‘H NMR (CDCI3) 8 ppm: 3.92 (s, 3H), 6.4 (bs,1H), 7.1 (m, 2H), 7.8 (m, 2H), 8.5 (s,1H).

At the same time, in my other blogs, there are other synthetic methods of this type of compound, Methyl 3-amino-6-bromopyrazine-2-carboxylate, and friends who are interested can also refer to it.

Reference:
Patent; SYNGENTA PARTICIPATIONS AG; SYNGENTA LIMITED; WO2005/123733; (2005); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 56423-63-3, 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 56423-63-3 as follows.

Ethyl 5-(4,4,5,5-tetramethyl-l,3,2-dioxaborolan-2-yl)-l-{2-[4-(trifluoromethoxy)phenoxy]ethyl}- lH-indole-2-carboxylate (34 mg, 0.065 mmol), 2-bromoprazine (21 mg, 0.13 mmol), K2C03 (27 mg, 0.2 mmol) and S Phos (2.7 mg, 0.006 mmol) were combined in 1.0 mL of dioxane in a flask. The reaction was degassed and filled with nitrogen. Water (0.2 mL) was added and purged again with nitrogen. Palladium acetate (0.7 mg, 0.003 mmol) was added, and the reaction was heated to 90C overnight. EtOAc was added and the crude mixture was filtered through a pad of Celite. The volatiles were concentrated in vacuo, and the reaction was purified on reverse phase HPLC (25-55% ACN in H20 (w/ 0.1% TFA)) to yield the title product. HRMS: Calc forC22H17F3N304 444.1171. Found 444.1 167

According to the analysis of related databases, 56423-63-3, the application of this compound in the production field has become more and more popular.

Reference:
Patent; MERCK SHARP & DOHME CORP.; HANNEY, Barbara; MANLEY, Peter; RUDD, Michael, T.; SANDERS, John, M.; STACHEL, Shawn, J.; HENZE, Darrell; WO2013/9582; (2013); 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. 58139-03-0, name is 2-Iodo-6-methoxypyrazine, A new synthetic method of this compound is introduced below., Formula: C5H5IN2O

2. 3-[2-(6-Methoxypyrazin)yl]-1-azabicyclo[2.2.2]octan-3-ol t-Butyllithium (20 ml of a 1.7M solution in pentane, 35.3 mmol) was added dropwise to a rapidly stirred solution of 2-methoxy-6-iodopyrazine (4.17 g, 17.6 mmol) in ether (80 ml), at -40° C. After 0.25 h a solution of quinuclidinone (2.21 g, 17.6 mmol) in ether (60 ml) was added dropwise and the reaction mixture warmed to room temperature and stirred for 2 h. Water (35 ml) was added and extracted with ethylacetate (4*100 ml). The combined extracts were dried (Na2 SO4), the solvent removed under vacuum and, the residue chromatographed through alumina, eluding with dichloromethane/methanol (93:7) to give 3-[2-(6-methoxypyrazin)yl]-1-azabicyclo [2.2.2]octan-3-ol (1.65 g); delta (360 MHz, CDCl3) 1.37-1.51 (3H,m, –CH2 and CH of CH2); 1.70-1.90(1H, brs, OH); 1.94-1.96-(1H,m,CH); 2.20-2.32(1H,m,CH of CH2); 2.80-3.10(5H,m,2*CH2 and CH of CH2) 3.74(1H,dd, J=2 and 14.6 Hz, CH of CH2); 3.99(3H,s,Me); 8.15(1H,s,pyrazine-H); 8.39(1H,s,pyrazine-H).

The synthetic route of 58139-03-0 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Merck Sharp & Dohme Limited; US5260293; (1993); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 57948-41-1, These common heterocyclic compound, 57948-41-1, name is 3-Bromoimidazo[1,2-a]pyrazine, 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.

3-Bromoimidazo[1 ,2-a]pyrazine (1.66 g, 7.13 mmol, Intermediate 2), sodium carbonate (3.78 g, 35.6 mmol) and phenylboronic acid (1.043 g, 8.55 mmol) were dissolved in 1 ,2-dimethoxyethane (DME) (40 ml) and water (20 ml). Bis(triphenylphosphine)palladium (II) chloride (0.250 g, 0.356 mmol) was added and the biphasic solution heated at 80 0C for 16 h. The aqueous phase was extracted with ethyl acetate (3 x 100ml) and the combined extracts washed with saturated sodium bicarbonate solution (100 ml), water (100 ml), brine (100 ml) and dried by passing through a hydromatrix cartridge (Varian). The filtrate was concentrated in vacuo to afford a crude oil (2.44g). The crude product was purified by flash chromatography (Biotage SP4, 40+M, eluting with a 0-100% gradient of ethylacetate in hexane) – (the product elutes in 100% ethyl acetate), to afford 3- phenylimidazo[1 ,2-a]pyrazine (1.22 g, 6.25 mmol, 88 % yield). LC/MS [M+H]+ = 196, retention time = 1.63 minutes (5 minute method).

Statistics shows that 3-Bromoimidazo[1,2-a]pyrazine is playing an increasingly important role. we look forward to future research findings about 57948-41-1.

Reference:
Patent; GLAXO GROUP LIMITED; DEAN, David Kenneth; MUNOZ-MURIEDAS, Jorge; SIME, Mairi; STEADMAN, Jon Graham Anthony; THEWLIS, Rachel Elizabeth Anne; TRANI, Giancarlo; WALL, Ian David; WALTER, Daryl Simon; WO2010/125101; (2010); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 1245644-42-1, A common heterocyclic compound, 1245644-42-1, name is 6-Bromo-3-iodoimidazo[1,2-a]pyrazine, molecular formula is C6H3BrIN3, 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.

Step 1 : To a solution of 6-bromo-3-iodoimidazo[l ,2-a]pyrazine (3.00 g, 9.26 mmol) in DMF (20 mL), was added Na2C03 (2.46 g, 23.2 mmol), 4-chlorophenylboronic acid (1.60 g, 10.2 mmol) and Pd(PPh3)4 (214 mg, 0.18 mmol). The resulting mixture was stirred at 80 C for 18 h under inert atmosphere and was concentrated under reduced pressure. The residue was purified by column chromatography (silica gel, eluent Hex/EtOAc 3:2) to afford 6-bromo-3- (4-chlorophenyl)imidazo[l,2-a]pyrazine (930 mg, 32%) as a yellow solid. 1H NMR (400 MHz, CDC13) delta 9.03 (d, J= 1.2 Hz, 1H), 8.36 (d, J= 1.2 Hz, 1H), 7.91 (s, 1H), 7.54 (q, J =12.3 Hz, 4H); MS (ESI) m/z 308 [C13H7BrN4 + H]+.

The synthetic route of 1245644-42-1 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; AGENCY FOR SCIENCE, TECHNOLOGY AND RESEARCH; NACRO, Kassoum; DURAISWAMY, Athisayamani, Jeyaraj; CHENNAMANENI, Lohitha, Rao; WO2013/147711; (2013); 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. 5521-58-4, name is 5-Methylpyrazin-2-amine, A new synthetic method of this compound is introduced below., Formula: C5H7N3

Intermediate 2: 3-[6-(azetidine-1-carbonyl)pyridin-3-yl]oxy-N-(5-methylpyrazin-2-yl)-5-phenylmethoxy-benzamide 1-Chloro-N,N,2-trimethyl-prop-1-en-1-amine (2.4 mL, 18 mmol) was added to a solution of 3-[6-(azetidine-1-carbonyl)pyridin-3-yl]oxy-5-phenylmethoxy-benzoic acid (Intermediate 3) (6.19 g, 15 mmol) in DCM (100 mL) and stirred at ambient temperature for 30 minutes. Further 1-chloro-N,N,2-trimethyl-prop-1-en-1-amine (0.24 mL, 1.8 mmol) was added and stirring continued for 20 minutes. 5-Methylpyrazin-2-amine (CAS no. 5521-58-4) (3.34 g, 31 mmol) and pyridine (2.5 mL, 31 mmol) were added and the reaction stirred for a further 16 hours. The solvent was removed under reduced pressure. The residue was dissolved in ethyl acetate (350 mL), washed with water (2*100 mL) and brine (100 mL), dried (MgSO4), and evaporated under reduced pressure. The residue was purified by flash chromatography, eluding with a gradient of 50-75% ethyl acetate in isohexane, to afford the product (4.01 g, 53%). 1H NMR delta (400 MHz, CDCl3) 2.28 (quintet, 2H), 2.49 (s, 3H), 4.18 (t, 2H), 4.63 (t, 2H), 5.05 (s, 2H), 6.78 (s, 1H), 7.10 (s, 1H), 7.25-7.37 (m, 7H), 8.04 (d, 1H), 8.07 (s, 1H), 8.25 (s, 2H), 9.46 (s, 1H); m/z 496 (M+H)+.

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; US2008/171734; (2008); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem