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. 123-32-0, name is 2,5-Dimethylpyrazine, A new synthetic method of this compound is introduced below., Safety of 2,5-Dimethylpyrazine

General procedure: A mixture of AgNO3 (0.051 g, 0.3 mmoL), H2ntph (0.063 g, 0.3mmol) and pyz (0.024 g, 0.3 mmoL) were dissolved in H2O/acetonitrile(10 mL, 1:1), after stirred for 20 min in air and then the mixturewas transferred to a 25 mL stainless steel reactor and heatedto 110 C for 72 h. And then the reaction system was cooled toroom temperature, colorless needle crystals of 1 were obtained.Yield based on Ag: 72%.

The synthetic route of 123-32-0 has been constantly updated, and we look forward to future research findings.

Reference:
Article; Yang, Yuan-Yuan; Zhou, Lin-Xia; Zhu, Hong-Lin; Li, Wen-Ying; Zheng, Yue-Qing; Polyhedron; vol. 148; (2018); p. 161 – 170;,
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 55557-52-3 as follows. Computed Properties of C5H2ClN3

General procedure: Compounds 5-10 (Supplemental Figure 6A, Scheme 1), 12-15 (Supplemental Figure 6B, Scheme 2), and 17, 18 (Supplemental Figure 6C, Scheme 3) were prepared by a modified procedure as reported by Kayser F. et al. (ref 1) and Chen Z. et al. (ref. 2). To a solution of the corresponding thiol, or phenol 4 (0.85 g, 5.0 mmol) in 15 ml DMF (N, N-Dimethylformamide) 3-chloropyrazine-2-carbonitrile (0.66 g, 4.76 mmol) and Na2CO3 (1.01 g, 9.52 mmol), or substituted chrolopyridines, or chlorobenzenes, were added respectively and the resulting mixture was refluxed at 80 C for 12 h. The DMF was evaporated at reduced pressure and the compound A residue was recrystallized from ethyl acetate. The rest of the compounds were purified by flash chromatography on silica gel with ethyl acetate:hexanes (5-100% gradient).

According to the analysis of related databases, 55557-52-3, the application of this compound in the production field has become more and more popular.

Reference:
Article; Freeman, Lita A.; Demosky, Stephen J.; Konaklieva, Monika; Kuskovsky, Rostislav; Aponte, Angel; Ossoli, Alice F.; Gordon, Scott M.; Koby, Ross F.; Manthei, Kelly A.; Shen, Min; Vaisman, Boris L.; Shamburek, Robert D.; Jadhav, Ajit; Calabresi, Laura; Gucek, Marjan; Tesmer, John J. G.; Levine, Rodney L.; Remaley, Alan T.; Journal of Pharmacology and Experimental Therapeutics; vol. 362; 2; (2017); p. 306 – 318;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

21279-62-9, name is 3-Chloropyrazine-2-carboxamide, 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. HPLC of Formula: C5H4ClN3O

General procedure: Compounds 1-6 were prepared according to conventional organic synthesis methods. 3-Chloropyrazine-2-carboxamide (1.27 mmol) was dissolved in THF (20 mL) in a round bottom flask and after that treated with two equivalents of the corresponding benzylamine and an equimolar amount of triethylamine. The reaction was conducted with continuous stirring and heating (70 C) under reflux in an oil bath for 15 h. Compounds 7-15 were synthesised using a microwave reactor with a focused field. 3-Chloropyrazine-2-carboxamide (1.27 mmol) was put into a thick-walled tube together with the corresponding benzylamine (2.54 mmol), pyridine (1.27 mmol), methanol (approx. 5 mL) and a magnetic stir bar and then sealed with a special cap. The reaction parameters were set according to the previously published paper as follows-140 C, 30 min, 200 W [29]. Reaction progress was checked by TLC (hexane:ethyl acetate-1:1). Regardless of the synthesis method used,all reaction mixtures were adsorbed on silica and subjected to preparative flash chromatography (hexane and ethyl acetate, gradient elution, detection wavelengths 260 nm and 280 nm). Products were recrystallized from ethanol or ethanol and water if necessary. All final substances were chemically characterized (1H-NMR, 13C-NMR, IR, melting point and elemental analysis).

The synthetic route of 21279-62-9 has been constantly updated, and we look forward to future research findings.

Reference:
Article; Jandourek, Ondrej; Tauchman, Marek; Paterova, Pavla; Konecna, Klara; Navratilova, Lucie; Kubicek, Vladimir; Holas, Ondrej; Zitko, Jan; Dolezal, Martin; Molecules; vol. 22; 2; (2017);,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 875781-43-4, A common heterocyclic compound, 875781-43-4, name is 2-Bromo-5H-pyrrolo[2,3-b]pyrazine, molecular formula is C6H4BrN3, 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 commercially available 2-bromo-5H-pyrrolo[2,3-b]pyrazine (1.00 g, 5.05 mmol) in N,N-dimethylformamide (10 mL) was added Cs2C03 (2.50 g, 7.67 mmol) and [2-(chloromethoxy)ethyl]trimethylsilane (1.26 g, 7.55 mmol). The reaction mixture was stirred overnight at room temperature and concentrated under vacuum. The residue was purified by flash chromatography on silica gel (solvent: 1/10 ethyl acetate/petroleum ether). Appropriate fractions were combined and evaporated to afford 2-bromo-5-[[2-(trimethylsilyl)ethoxy]methyl]-5H-pyrrolo[2,3-b]pyrazine (1.50 g, 90%) as a yellow solid. LC/MS (Method D, ESI): [M+H]+ = 328.0, RT = 1.23 min.

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; F. HOFFMANN-LA ROCHE AG; GENENTECH, INC.; ZAK, Mark; ROMERO, F. Anthony; YUEN, Po-wai; HANAN, Emily J.; (139 pag.)WO2018/166993; (2018); A2;,
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. 2423-65-6, name is Pyrazine 1-oxide, A new synthetic method of this compound is introduced below., SDS of cas: 2423-65-6

General Procedure 2:; Palladium-Catalyzed Direct Arylation with Aryl Chlorides and Bromides.; To a dried flask was added the diazine N-oxide (1.0 to 3.0 equiv.), K2CO3 (2.0 equiv.), Pd(OAc)2 (5 mol %) and HP(t-Bu)3BF4 (15 mol %). If the arylhalide is a solid, it is added at this point (1.0 equiv.). The flask and its contents were then purged under nitrogen for 10 minutes. If the aryl halide is a liquid, it is added via syringe after purging, followed by the addition of degassed dioxane (to produce a reaction concentration of 0.3 M relative to the halide). The reaction mixture was then heated at 110 C. until the reaction was complete, after which the volatiles were removed under reduced pressure and the residue was purified via silica gel column chromatography.; 2-p-Tolylpyrazine N-oxide (81) Synthesised according to general procedure 2 employing the corresponding aryl bromide and chloride or 60 with the corresponding aryl iodide. Purification via silica gel column chromatography using 100% DCM then a mixture of 20% Acetone/DCM gave a white solid, 72% (from the bromide), 75% (from the chloride) and 77% (from the iodide). 1H NMR (300 MHz, CDCl3, 293K, TMS): delta 8.63 (1H, s), 8.37 (1H, s), 8.20 (1H, s), 7.72 (2H, d, J=8.1 Hz), 7.33 (2H, d, J=7.8 Hz), 2.43 (3H, s). 13C NMR (75 MHz, CDCl3, 293K, TMS): 148.2, 145.2, 144.6, 140.8, 134.2, 129.8, 129.0, 125.9, 21.5.

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; University of Ottawa; US2008/132698; (2008); 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. 6863-73-6, name is 3-Chloropyrazin-2-amine, A new synthetic method of this compound is introduced below., Recommanded Product: 6863-73-6

N. 1 -IMIDAZO[ 1 ,2-A]PYRAZIN-8-YL-3 -TRIFLUOROMETHYL- IH-P YRAZOLE-4-C ARBOXYLIC ACID (I -P YRIDIN-3 -YL-CYCLOHEXYLMETHYL)-AMIDE (COMPOUND 14); Step 1. 8-Chloro-imidazol[l,2-a]pyrazine; HBr (48% in H2O) is added to a solution of 2-amino-3-chloropyrazine (1.2 g, 9.26 mmol) and BrCH2CH(OEt)2 (1.6 mL, 10 mmol) in MeOH and H2O (5 mL and 10 mL) at RT. The mixture is stirred for 24 h at RT and then heated to 40 C for 48 h. The pH is adjusted to 7 with sat. Na2Ctheta3. The mixture is extracted with CH2Cl2. The organic phase is dried over anhydrous Na2SO^ The product is purified by silica gel column chromatography (4%MeOH in CH2Cl2) to give the title compound as an off white solid.

The synthetic route of 6863-73-6 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; NEUROGEN CORPORATION; WO2009/12482; (2009); A2;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 13134-31-1, These common heterocyclic compound, 13134-31-1, name is 2,3-Diaminopyrazine, 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.

A mixture of 2,3-diaminopyrazine (55mg, 0.5mmol) and methyl 1-({5-chloro-2-[(2- methylpropyl)oxy]phenyl}methyl)-5-methyl-1/-/-pyrazole-3-carboximidoate hydrochloride (186mg, O.deltammol) in ethanol (4ml) was stirred and refluxed for 4 hours. The solid which separated was filtered, dissolved in hot methanol and 1 M hydrogen chloride in ether (0.5ml) added. The solution was evaporated to dryness and the residue triturated with ether to give the title compound as an off-white solid (17mg). LC/MS Rt 3.10, [MH]+ 397.2, 399.2

The synthetic route of 13134-31-1 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; GLAXO GROUP LIMITED; WO2006/114313; (2006); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 912773-21-8,Some common heterocyclic compound, 912773-21-8, name is 2-Bromo-5-chloropyrazine, molecular formula is C4H2BrClN2, 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 tert-butyl (3aR, 5s,6a5)-5-aminohexahydrocyclopenta[c]pyrrole-2( 1 H)-carboxylate (274 mg, 1.21 mmol) in NIVIP (4.5 mL) was added 2-bromo-5-chloropyrazine (585 mg, 3.02 mmol) and J7N- diisopropylethylamine (0.63 mL, 3.63 mmol). The mixture was stirred at 180 C under microwave irradiation for 1 h. Solids were removed by syringe filtration, and crude residue was purified by RP-HPLC (20-70% MeCN in 0.05% NH4OH aqueous solution over 20 mm). Fractions containing product were combined and concentrated to give the title compound as a brown oil (148 mg, 32%). ES-MS [M+H]b = 383.2.

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

Reference:
Patent; VANDERBILT UNIVERSITY; LINDSLEY, Craig, W.; CONN, P., Jeffrey; ENGERS, Darren, W.; ENGERS, Julie, L.; TEMPLE, Kayla, J.; BENDER, Aaron, M.; BAKER, Logan A.; (221 pag.)WO2019/79783; (2019); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 14508-49-7, These common heterocyclic compound, 14508-49-7, name is 2-Chloropyrazine, 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.

The starting compound 3-chloropyrazine-2-carboxamide was synthesized using two published procedures. The first method was classified as less effective and was based on the homolytic amidation of 2-chloropyrazine. Thus, 2-chloropyrazine (0.17 mol) was dissolved in formamide (3.7 mol), heated to 90 C and ammonium peroxodisulphate (0.18 mol) was added portionwise over one hour period. This mixture reacted for another one hour at 90 C and then it was left to stand for 24 h at laboratory temperature. Dilution with 100 mL of water was followed by filtration and this filtrate was extracted continuously with chloroform for 16 h [34,42]. The mixture of three positional isomers was separated by flash chromatography using silica gel as stationary phase. The second process used 3-chloropyrazine-2-carbonitrile, which was submitted to partial hydrolysis of the nitrile group. The powdered carbonitrile (0.104 mol) was added little by little into the reaction mixture of concentrated hydrogen peroxide (0.95 mol) and water (195 mL) heated to 50 C. The pH was adjusted and regulated around a value of 9 using an 8% solution of sodium hydroxide and the temperature of the reaction was regulated between 55 and 60 C. The reaction was stopped after 2.5 h and was cooled to 5 C. Newly-emerged crystals were removed by suction and recrystallized from ethanol [42].

Statistics shows that 2-Chloropyrazine is playing an increasingly important role. we look forward to future research findings about 14508-49-7.

Reference:
Article; Jandourek, Ondrej; Dolezal, Martin; Kunes, Jiri; Kubicek, Vladimir; Paterova, Pavla; Pesko, Matus; Buchta, Vladimir; Kralova, Katarina; Zitko, Jan; Molecules; vol. 19; 7; (2014); p. 9318 – 9338;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 19847-12-2, 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 19847-12-2 as follows.

General procedure: Sodium metal (23 mg) was dissolved in absolute methanol (20 ml) and was labeled as sodium methoxide solution in methanol. 2-Cyanopyridine (0.210 ml, 2 mmol) was dissolved in absolute methanol (10 ml) and to it was added sodium methoxide solution (0.5 ml) prepared above, the reaction contents were stirred at room temperature for 2 h. 4-(2-Aminoethyl) morpholine (0.26 ml, 2 mmol) was added to the reaction mixture. The reaction contents were heated under reflux for 8 h. Solvent was removed under reduced pressure and to the residue left behind was added diethyl ether, solid so obtained was filtered and washed with diethyl ether to give crude product. This crude product was purified by crystallization from ethyl acetate/methanol to give pure N-(2-morpholin-4-yl-ethyl)-pyridine-2-carboxamidine (3a).

According to the analysis of related databases, 19847-12-2, the application of this compound in the production field has become more and more popular.

Reference:
Article; Arya, Surbhi; Kumar, Nikhil; Roy, Partha; Sondhi; European Journal of Medicinal Chemistry; vol. 59; (2013); p. 7 – 14;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem