Pyrazines

Application 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.

General procedure: Used for N-benzyl derivatives 1-8. The starting 3-aminopyrazine-2-carboxylic acid(Sigma-Aldrich, Schnelldorf, Germany; 2.2 g; 15.8 mmol) in methanol (250 mL) was cooled downto 0 C and concentrated H2SO4 (3.2 mL) was added. The reaction mixture was stirred for 48 h atrt. Subsequently the reaction mixture was poured into water (27 mL) and alkalized by NaHCO3(approx. 6.3 g) to pH = 7. The precipitate was filtered off and collected as white-brown solid toobtain methyl 3-aminopryzine-2-carboxylate [32]. Methyl 3-aminopyrazine-2-carboxylate (100 mg;0.65 mmol) in methanol (2 mL) along with substituted benzylamine (1.95 mmol; 3 equiv) and NH4Cl(10 mg; 0.19 mmol; 0.1 equiv) [33] were put into reaction tube used for microwave assisted synthesiswith a magnetic stirrer. Reaction was performed in a CEM Discover microwave reactor with a focusedfield in pressurized vials with the following settings: 130 C, 90 W and 40 min. The progress of thereaction was checked using TLC (Merck Silica 60 F254) developed by in hexane/ethyl-acetate 2:1 system.The reaction mixture was adsorbed to silica gel and purified by flash chromatography (Teledyne IscoInc.,) using silica (irregular, 40-63 m) as a stationary phase and gradient elution EtOAc in hexane0-100%, with respect to the expected lipophilicity of the product.

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:
Article; Bouz, Ghada; Semelkova, Lucia; Jand?ourek, Ond?ej; Kone?na, Klara; Paterova, Pavla; Navratilova, Lucie; Kubi?ek, Vladimir; Kune?, Ji?i; Dole?al, Martin; Zitko, Jan; Molecules; vol. 24; 7; (2019);,
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. 762240-92-6, name is 3-(Trifluoromethyl)-5,6,7,8-tetrahydro-[1,2,4]triazolo[4,3-a]pyrazine hydrochloride, A new synthetic method of this compound is introduced below., Safety of 3-(Trifluoromethyl)-5,6,7,8-tetrahydro-[1,2,4]triazolo[4,3-a]pyrazine hydrochloride

15 g (45 mmol) of the compound (2) (R) -3- (tert-butoxycarbonylamino) -4- (2,4,5-trifluorophenyl) butyric acid,Compound (3) 3- (Trifluoromethyl) -5,6,7,8-tetrahydro- [1,2,4] triazolo [4,3-a] pyrazine hydrochloride 11.3 g(49.5mmo 1),HOBT 7.3 g (54 mmol) was added to 150 ml of dichloromethane.At room temperature,14.4 g (135 mmol) of 2,6-dimethylpyridine was added,Then add 10.3 g (54 mmol) of EDC-HC1,The mixture was stirred at room temperature for 3 hours.Add 5% sodium carbonate aqueous solution to adjust rhoH- = 9,Layered,The methylene chloride layer was washed with 150 ml of water,Layered,The methylene chloride layer was dried over anhydrous sodium sulfate,filter,The filtrate was evaporated at 35 C under reduced pressure to give 21.7 g of the compound (1)Yield 95%HPLC 94.5%.

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; Zhejiang Huahai Pharmaceutical Co., Ltd; GE, JIANFENG; YAN, FENGFENG; (6 pag.)CN102603749; (2017); B;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

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., COA of Formula: C6H7N3O2

3-Aminopyrazine-2-carboxylic acid methyl ester (2.5 g, 16.3 mmol), di-tert.-butyldicarbonate (7.5 g, 34.4 mmol) and 4-(N,N-dimethylamino)pyridine (0.1 g, 0.8 mmol) were dissolved in 100 mL dichloromethane and refluxed for 4 hrs. The reaction mixture was cooled and extracted with sat. NaHCO3- solution and ethyl acetate. The organic extract was dried with sodium sulfate, filtered and evaporated. The crude product was purified by flash chromatography on silica gel (heptane/ethyl acetate 90:10->1:1 gradient). The desired compound was obtained as a white solid (4.7 g, 81percent), MS: m/e=354.0 (M+H+).

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 16298-03-6.

Reference:
Patent; Jaeschke, Georg; Kolczewski, Sabine; Porter, Richard Hugh Philip; Vieira, Eric; US2006/199828; (2006); 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 173253-42-4 as follows. Computed Properties of C4H3BrClN3

Example 6 2-Amino-5,7-dihydrofuro[3,4-b]pyrazine A mixture of 2-amino-5-bromo-6-chloro-pyrazine (21 mg, 0.10 mmol), tributyl{[tributylstannyl)methoxy]methyl}stannane according to Production Example 1-2 (62 mg, 0.10 mmol), tris(dibenzylideneacetone)dipalladium (9.2 mg, 0.010 mmol), X-Phos (19 mg, 0.040 mmol), and 1,4-dioxane (1.0 mL) was stirred while being heated to reflux for 20 hours. The resulting mixture was cooled to room temperature and then filtered through Celite and concentrated under reduced pressure. The residue was separated and purified by preparative thin-layer chromatography (ethyl acetate_heptane=5:1) to obtain the title compound (3.6 mg, 26% yield). 1H-NMR Spectrum (400 MHz, CDCl3) delta (ppm): 4.55 (br s, 2H), 4.87-5.13 (m, 4H), 7.83 (s, 1H).

According to the analysis of related databases, 173253-42-4, the application of this compound in the production field has become more and more popular.

Reference:
Patent; Eisai R&D Management Co., Lt.d; Tanaka, Keigo; Fukuyama, Takashi; Murai, Norio; Itano, Wataru; Hirota, Shinsuke; Iida, Daisuke; Azuma, Hiroshi; (32 pag.)US2016/168176; (2016); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

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. 681249-57-0, name is 2-(Trifluoromethyl)-5,6,7,8-tetrahydro[1,2,4]triazolo[1,5-a]pyrazine belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below. Recommanded Product: 2-(Trifluoromethyl)-5,6,7,8-tetrahydro[1,2,4]triazolo[1,5-a]pyrazine

2-Fluoro-5-[(4-oxo-3H-phthalazin-1-yl)methyl]benzoic acid 1a (780 mg, 2.65 mmol) was dissolved in 15 mL of N, N-dimethylformamide, followed by addition of O-(1-benzotriazolyl)-N, N, N’, N’-tetramethyluronium hexafluorophosphate (1.80 g, 4.77 mmol), 2-(trifluoromethyl)-5,6,7,8-tetrahydro-[1,2,4]triazolo[1,5-a]pyrazine 19a (560 mg, 2.92 mmol, prepared according to a known method disclosed by ‘patent application ‘) and N, N-diisopropylethylamine (1.4 mL, 7.95 mmol). After stirring for 12 hours, the reaction mixture was concentrated under reduced pressure, added with 30 mL of H2O, extracted with ethyl acetate (30 mL*3). The organic phase was combined, washed with saturated sodium chloride solution (20 mL), dried over anhydrous sodium sulfate and filtered. The filtrate was concentrated under reduced pressure and the resulting residue was purified by thin layer chromatography with elution system A to obtain 4-[[4-fluoro-3-[2-(trifluoromethyl)-6,8-dihydro-5H-[1,2,4]triazolo[1,5-a]pyrazine-7-carbonyl]phenyl]methyl]-2H-phthalazin-1-one 19 (205 mg, yield 16.4%) as a light yellow solid. MS m/z (ESI): 473.1 [M+1] 1H NMR (400 MHz, CDCl3): delta 10.67 (br. s, 1H), 8.48 (s, 1H), 7.77 (m, 3H), 7.42 (m, 2H), 7.11 (t, 1H), 5.10 (s, 1H), 4.75 (s ,1H),4.39 (s, 2H), 4.32 (d, 3H), 3.88 (s, 1H)

The synthetic route of 681249-57-0 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Jiangsu Hansoh Pharmaceutical Co., Ltd.; TANG, Pengcho; LI, Xin; LI, Xiangqin; CHEN, Yang; WANG, Bin; ZHU, Zhe; EP2604610; (2013); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Some common heterocyclic compound, 1245644-42-1, name is 6-Bromo-3-iodoimidazo[1,2-a]pyrazine, molecular formula is C6H3BrIN3, 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: 6-Bromo-3-iodoimidazo[1,2-a]pyrazine

General procedure: 6-Bromo-3-thiophen-2-yl-imidazo[1,2- a]pyrazine 18*c Note: An additional 1 mol% of Palladium Acetate and triphenylphosphine was added after 12 hours to increase the yield of the reaction. 1H-NMR (400 MHz, CDCl3): delta = 8.94 (s, 1 H), 8.49 (s, 1 H), 7.95 (s, 1 H), 7.55 (d, J =5.2Hz, 1 H), 7.38 (d, J =3.2Hz, 1 H), 7.27 (s, 1H). Yield: 42.3%.

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 1245644-42-1, its application will become more common.

Reference:
Patent; Max-Planck-Gesellschaft zur Foerderung der Wissenschaften e.V.; Ullrich, Axel; Falcenberg, Mathias; EP2818471; (2014); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

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. 762240-92-6, name is 3-(Trifluoromethyl)-5,6,7,8-tetrahydro-[1,2,4]triazolo[4,3-a]pyrazine hydrochloride, This compound has unique chemical properties. The synthetic route is as follows., Quality Control of 3-(Trifluoromethyl)-5,6,7,8-tetrahydro-[1,2,4]triazolo[4,3-a]pyrazine hydrochloride

4.7 (R)-tert-Butyl 4-oxo-4-(3-(trifluoromethyl)-5,6-dihydro-[1,2,4]triazolo[4,3-a]pyrazin-7(8H)-yl)-1-(2,4,5-trifluorophenyl)butan-2-ylcarbamate 9 (R)-3-(tert-Butoxycarbonylamino)-4-(2,4,5-trifluorophenyl)butanoic acid 7 (200 mg, 0.59 mmol) and 3-(trifluoromethyl)-5,6,7,8-tetrahydro-[1,2,4]triazolo[4,3-a]pyrazinehydrochloride 8 (115 mg, 0.59 mmol) in anhydrous DCM (3 mL) were cooled to 0 C. To that solution was added HOBT (96 mg, 0.7 mmol), followed by EDC·HCl (134 mg, 0.7 mmol) and DIEPA (152 mg, 1.18 mmol). After being stirred for 24 h, DCM was evaporated, and the viscous residue was partitioned between ethyl acetate and saturated aqueous NaHCO3 solution. The aqueous layer was extracted with ethyl acetate. The combined organic phase was washed with brine, dried over Na2SO4, and concentrated. The crude product was purified by column chromatography eluting with 80% ethyl acetate in hexane to afford 9 as a white powder (280 mg, 92% yield). Mp: 189-192 C; {lit. 8a mp: 188-191 C}; [alpha]D25.1 = +20.8 (c 0.11, CHCl3); {lit. 8a [alpha]D20 = +22.2 (c 1.0, CHCl3)}; 1H NMR (500 MHz, CDCl3) delta 1.35 (s, 9H), 2.93-2.67 (m, 4H), 4.17-3.97 (m, 5H), 4.92 (s, 1H), 5.07-5.00 (m, 1H), 5.28 (s, 1H), 6.88 (s, 1H), 7.08-7.06 (d, J = 6.36 Hz, 1H). 13C NMR (125 MHz, CDCl3) delta 28.2, 32.9, 36.7, 38.0, 39.2, 41.8, 42.6, 43.1, 43.6, 48.2, 48.4, 79.7, 105.2, 105.3, 105.4, 105.5, 117.1, 119.0, 119.1, 121.4, 143.7, 144.0, 145.6, 147.7, 147.9, 149.4, 149.9, 150.2, 155.2, 157.1, 169.5, 169.9; MS (ESI) m/z: 507.9 (M+H)+. HRMS (ESI) (M+H)+: calcd for C21H23F6N5O3: 508.1778; found: 508.1778.

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 762240-92-6.

Reference:
Article; Subbaiah; Haq, Wahajul; Tetrahedron Asymmetry; vol. 25; 13-14; (2014); p. 1026 – 1030;,
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 108-50-9 as follows. Computed Properties of C6H8N2

1-Bromo-2,5-pyrrolidinedione (0.055 mol) and then dibenzoyl peroxide (cat.quant.) were added to a mixture of 2,6-dimethylpyrazine (0.05 mol) in CCl4 (100ml). The mixture was stirred and refluxed for 4 hours, stirred at room temperature under N2 flow overnight, cooled on an ice bath and filtered. The filtrate was evaporated, to give residue 1. NaH (0.04 mol) was added to a solution of intermediate (1) (0.04 mol) in DMF (150ml). The mixture was stirred at room temperature under N2 flow for 1 hour. Residue 1 was dissolved in DMF (50ml) and added dropwise to the mixture. The mixture was stirred at 50C overnight. DMF was evaporated. The residue was taken up in H2O and the mixture was extracted with CH2Cl2. The organic layer was separated, dried, filtered and the solvent was evaporated. The residue was purified by column chromatography over silica gel (eluent: CH2Cl2/CH3OH 98/2). The pure fractions were collected and the solvent was evaporated. Yield: 6.82g of intermediate (2) (32%).

According to the analysis of related databases, 108-50-9, the application of this compound in the production field has become more and more popular.

Reference:
Patent; JANSSEN PHARMACEUTICA N.V.; EP1418175; (2004); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 74290-67-8,Some common heterocyclic compound, 74290-67-8, name is 2-Amino-5-bromo-3-methylpyrazine, molecular formula is C5H6BrN3, 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 solution of 5-bromo-3-methyl-pyrazin-2-amine (1000 mg, 5.32 mmol), phenol (650 mg, 6.91 mmol), Cs 2CO 3 (2600 mg, 7.98 mmol), CuI (203 mg, 1.06 mmol), and N, N-dimethylglycine (110 mg, 1.06 mmol) in dioxane (5 mL) was degassed and heated to 90 under N 2 for 12 h. After cooling to room temperature, the mixture was diluted with EtOAc (100 mL) and water (100 mL) and the organic phase collected. The aqueous layer was extracted again with EtOAc (100 mL) and the combined organic layers were dried over anhydrous MgSO 4 and concentrated to dryness. The residue was purified by flash column chromatography to give the title compound as a yellow oil (533 mg, 49.8% yield). MS (ESI) : mass calcd. for C11H 11N 3O, 201.1 m/z found, 202.1 [M+H] +.

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 2-Amino-5-bromo-3-methylpyrazine, its application will become more common.

Reference:
Patent; JANSSEN PHARMACEUTICA NV; CAI, Min; ARORA, Nidhi; BACANI, Genesis M.; BARBAY, Joseph Kent; BEMBENEK, Scott D.; CHEN, Wei; DECKHUT, Charlotte Pooley; EDWARDS, James P.; GHOSH, Brahmananda; HAO, Baoyu; KREUTTER, Kevin D.; LI, Gang; TICHENOR, Mark S.; VENABLE, Jennifer D.; WEI, Jianmei; WIENER, John J. M.; WU, Yao; ZHU, Yaoping; ZHANG, Feihuang; ZHANG, Zheng; XIAO, Kun; (999 pag.)WO2018/103058; (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 143591-61-1 as follows. Product Details of 143591-61-1

To a solution of compound 102 (13.0 g, 55.9 mmol) in DMSO (150 mL) was added sodium methanethiolate (4.70 g, 67.08 mmol) as a DMSO solution (100 mL) at room temperature. The reaction mixture was stirred at 100 C. for 16 hours. The mixture was cooled to 25 C. and added to a brine solution (300 mL), and extracted with 10% IPA/dichloromethane (300 mL, 3×). The combined organic layer was dried over anhydrous sodium sulfate and concentrated. Purification by column chromatography (SiO2, ethyl acetate/hexanes (1:1)) afforded compound 103 as a yellow solid 10 g (70%). 1H-NMR (400 MHz, DMSO-d6 delta 8.15 (d, 1H), 7.88 (d, 1H), 7.83 (s, 1H), 2.6 (s, 3H).

According to the analysis of related databases, 143591-61-1, the application of this compound in the production field has become more and more popular.

Reference:
Patent; Schering Corporation; US2007/105864; (2007); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem