Tag: M.W=100-200

Reference of 91476-80-1, These common heterocyclic compound, 91476-80-1, name is 5,6,7,8-Tetrahydroimidazo[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.

Step 3 4-[[3-(6,8-dihydro-5H-imidazo[1,2-c]pyrazine-7-carbonyl)-4-fluoro-phenyl]methyl]-2H-phthalazin-1-one 2-Fluoro-5-[(4-oxo-3H-phthalazin-1-yl)methyl]benzoic acid 1a (323 mg, 1.08 mmol) was dissolved in 5 mL of N,N-dimethylformamide, followed by addition of O-(1-benzotriazolyl)-N,N,N’,N’-tetramethyluronium hexafluorophosphate (614 mg, 1.63 mmol), 5,6,7,8-tetrahydroimidazo[1,2-a]pyrazine 4c (200 mg, 1.63 mmol) and N, N-diisopropylethylamine (0.4 mL, 2.16 mmol). After stirring for 12 hours, the reaction mixture was concentrated under reduced pressure and the resulting residue was purified by thin layer chromatography with elution system A to obtain 4-[[3-(6,8-dihydro-5H-imidazo[1,2-c]pyrazine-7-carbonyl)-4-fluoro-phenyl]methyl]-2H-phthalazin-1-one 4 (10 mg, yield 2.3%) as a white solid. MS m/z (ESI): 404.1 [M+1] 1H NMR (400 MHz, CDCl3): delta 10.07 (br. s, 1H), 8.53 (d, 1H), 7.96 (m, 1H), 7.83 (m, 3H), 7.51 (m, 1H), 7.30 (m, 2H), 6.01 (t, 1H), 4.73 (d, 2H), 4.35 (s, 2H), 1.60 (m, 2H), 1.34 (m, 2H)

The synthetic route of 91476-80-1 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; JIANGSU HANSOH PHARMACEUTICAL CO., LTD.; Tang, Peng Cho; Li, Xin; Li, Xiangqin; Chen, Yang; Wang, Bin; Zhu, Zhe; US2013/131068; (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. 313339-92-3, name is 3,5-Dichloropyrazine-2-carbonitrile, A new synthetic method of this compound is introduced below., Safety of 3,5-Dichloropyrazine-2-carbonitrile

Step 1: To a mixture of 3,5-dichloropyrazine-2-carbonitrile (500 mg, 2.84 mmol) and D-valinamide HCl salt (476 mg, 3.12 mmol) in AcCN (10 mL) was added DIPEA (1.11 mL, 6.25 mmol). After stirring at room temperature for 4 h, it was diluted with EtOAc, washed with sat. NaHCO3, organic layer was separated and washed with brine, dried and concentrated to give (R)-2-(6-chloro-5-cyanopyrazin-2-ylamino)-3-methylbutanamide (740 mg).

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; Portola Pharmaceuticals, Inc.; Song, Yonghong; Xu, Qing; Jia, Zhaozhong J.; Kane, Brian; Bauer, Shawn M.; Pandey, Anjali; US2013/131040; (2013); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

4858-85-9, name is 2,3-Dichloropyrazine, 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. name: 2,3-Dichloropyrazine

Under a nitrogen atmosphere, in 25 ml substrate is added into the test tube reactor 3dam (0.2mmol, 29.6 mg), 1-chlorobutane (3.0mmol, 276.0 mg), PdCl2(dppf) (0.02mmol, 14.6 mg), DPPF (0.01mmol, 5.6 mg), Cs2CO3(0.3mmol, 195.0 mg), Na2S2O35H2O (0.5mmol, 248.0 mg), DMSO (4.0 ml) and glycol (0.1 ml). Heating the reaction system to 120 C for reaction. TLC detection after the reaction is ended, the system is cooled to room temperature. Hydrosolvent quenching reaction with saturated ammonium chloride, extracted with ethyl acetate (3*10 ml), column chromatography purification to obtain the product 3da (88%).

The synthetic route of 4858-85-9 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; East China Normal University; JIANG, XUE FENG; QIAO, ZONG JUN; (33 pag.)CN103848767; (2016); B;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

20721-17-9, name is 5-Methylpyrazin-2(1H)-one, 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. category: Pyrazines

2-HYDROXY-5-METHYLPYRAZINE (0.984g, 8.94 mmol) was refluxed in 15 mL PHOSPHOROXY- chloride for 1.5h. The reaction mixture was slowly poured into ice and adjusted to pH6 by addition of sodium carbonate. The mixture was extracted six times with ethyl acetate (50 mL each). The combined organic extracts were dried with sodium sulfate, filtered and eva- porated. The crude product was used without any further purification for the next step.

The synthetic route of 20721-17-9 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; F. HOFFMANN-LA ROCHE AG; WO2004/80998; (2004); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 25513-93-3, A common heterocyclic compound, 25513-93-3, name is 3-Methylpyrazine-2-carbaldehyde, molecular formula is C6H6N2O, 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-dimethylpyrazine (2Og, 18.5mmol), selenium dioxide (41.06g, 37mmol) and diatomeous earth (2Og) in EtOAc (500ml) was stirred and heated at 7O0C for 2 hours. The mixture was allowed to cool and the insoluble matter was removed by filtration EPO through diatomeous earth. The filtrate was washed with saturated aqueous sodium hydrogen carbonate solution and then saturated aqueous sodium chloride solution, dried (MgSO4) and the solvent removed by evaporation. The residue was suspended in water (100ml) and hydroxylamine (45ml of a 50% aqueous solution) was added. The mixture was stirred at ambient temperature for 18 hours and the mixture then extracted with EtOAc. The extracts were combined, washed with saturated aqueous sodium chloride solution, dried (MgSO4) and the solvent removed by evaporation. The residue was triturated with isohexane to give 3- methylpyrazine-2-carboxaldehyde oxime (9.65g, 38%); NMR Spectrum 2.67 (s, 3H), 8.23 (s, IH), 8.45-8.49 (m, 2H), 11.87 (s, IH).

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; ASTRAZENECA UK LIMITED; WO2006/106307; (2006); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Some common heterocyclic compound, 13924-94-2, name is Methyl 5-aminopyrazine-2-carboxylate, molecular formula is C6H7N3O2, 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. Computed Properties of C6H7N3O2

19.3. Methyl 5-amino-6-bromopyrazine-2-carboxylate; Add 1.79 g (10.05 mmol) of N-bromosuccinimide to a solution of 1.4 g (9.14 mmol) of methyl 5-aminopyrazine-2-carboxylate in 10 mL of acetonitrile. Stir the reaction mixture for 2 h at 20 C. then distribute in 100 mL of EtOAc/water 1:1 mixture. Wash the organic phase with 2¡Á50 mL of water, dry over Na2SO4 and concentrate under reduced pressure. Purify the residue obtained by silica gel column chromatography, eluting with a cyclohexane/EtOAc gradient from 0 to 50% of EtOAc. After concentration under reduced pressure, we obtain 1.66 g of methyl 5-amino-6-bromopyrazine-2-carboxylate in the form of yellow wax.Yield=78%

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 13924-94-2, its application will become more common.

Reference:
Patent; Sanofi Aventis; US2009/318473; (2009); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 6863-73-6, These common heterocyclic compound, 6863-73-6, name is 3-Chloropyrazin-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.

Second generation imidazo[1,2-a]pyrazineinhibitors, variants at 2- and 6-positions.8-Chloroimidazo[1,2-a]pyrazine 2-Amino-3-chloropyrazine (200 mg, 1.54mmol) and NaHCO3 (162 mg, 1.93 mmol) were suspended in tBuOH. Chloroacetaldehyde (50% w/v in H2O;200 muL, 1.54 mmol) was added and the reaction mixture was stirred under refluxfor 40 h. The reaction was then cooledto RT and solvent removed in vacuo. The residual material was taken up in CH2Cl2(100 mL) washed H2O (40 mL) and brine (40 mL), dried (MgSO4),filtered and concentrated in vacuo. Flash chromatography (applied in pet. ether;eluted 3:1 to 2:1 to 1:3 pet. ether/EtOAc) afforded the title compound as anoff white solid (118 mg, 0.773 mmol, 50%). Mpt: Decomposed before melting; Rf = 0.17 (2:1 EtOAc/pet.ether); IR (numax/cm-1, thin film): 3144, 3105, 1432; 1H NMR (600 MHz,(CD3)2SO): deltaH = 7.73 (d, J= 4.5 Hz, 1H, 6-H), 7.87 (d, J = 0.9 Hz, 1H, 2-H), 8.28 (d, J = 0.9Hz, 1H, 3-H), 8.66 (d, J = 4.5 Hz, 1H, 5-H); 13C NMR (150 MHz, (CD3)2SO): deltaC = 117.3 (C-3),120.8 (C-5), 127.3 (C-6), 135.5 (C-2), 137.1 (C-9), 141.7(C-8); LRMS m/z (CI+):154 [M(35Cl)+H]+, 156 [M(37Cl)+H]+;HRMS m/z (CI+): Found 154.0166 [M(35Cl)+H]+; C6H5ClN3requires154.0172.

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

Reference:
Article; Sayer, James R.; Walldn, Karin; Pesnot, Thomas; Campbell, Frederick; Gane, Paul J.; Simone, Michela; Koss, Hans; Buelens, Floris; Boyle, Timothy P.; Selwood, David L.; Waksman, Gabriel; Tabor, Alethea B.; Bioorganic and Medicinal Chemistry; vol. 22; 22; (2014); p. 6459 – 6470;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 313339-92-3, These common heterocyclic compound, 313339-92-3, name is 3,5-Dichloropyrazine-2-carbonitrile, 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.

(4-tert-butoxycarbonyl-aminophenyl) boronic acid pinacol ester (8.26 g) was added to a reaction vessel containing a magnetic stirrer in 3,5-dichloro-pyrazine-2-carbonitrile (5.0 g), 1,1 ‘-bis (diphenylphosphino) ferrocene-palladium (II) dichloride (1.68 g) and cesium carbonate (28.1 g) followed by 100 ml of dioxane and 10 ml of water were added and the mixture was heated to 100 C. with stirring.After 1 h, the reaction mixture was cooled to room temperature and then quenched with saturated sodium bicarbonate solution (100 ml) and extracted with EtOAc (3 ¡Á 200 ml) The combined organic phases were dried over sodium sulfate, The product was purified by flash chromatography on a silica gel using a mixture of EtOAc and heptane as the eluant and the product was recrystallized from methyl tert-butyl ether to give the crude product as a brown oil which was purified by flash chromatography After drying in vacuo, tert-butyl ester of [4- (6-chloro-5-cyano-pyrazin-2-yl) -phenyl] -carbamic acid was obtained as a pale yellow solid. 6.92 g (73%)

Statistics shows that 3,5-Dichloropyrazine-2-carbonitrile is playing an increasingly important role. we look forward to future research findings about 313339-92-3.

Reference:
Patent; SANOFI; NAZARE, MARC; HALLAND, NIS; SCHMIDT, FRIEDEMANN; WEISS, TILO; DIETZ, UWE; HOFMEISTER, ARMIN; CARRY, JEAN-CHRISTOPHE; (93 pag.)JP5827849; (2015); B2;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 56423-63-3,Some common heterocyclic compound, 56423-63-3, name is 2-Bromopyrazine, molecular formula is C4H3BrN2, 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 BB-7 (79 mg, 0.24 mmol), 2-bromopyrazine (48 mg, 0.319 mmol), t-BuOK (8 mg, 0.72 mmol, as 1.0 M solution in dry THF) and iPr-PEPPSI catalyst (9mg, 0.014 mmol) in toluene (3 mL) was heated at 70C in a microwave reactor for 1 h. Then, water was added and the RM was extracted with EtOAc.The volatiles were removed under reduced pressure and the residue was purified by CC (PF-3OSIHP/4G/ Cy IEtOAc) to yield the desired compound (23 mg, 23%).LC-MS (Method 2): m/z [M+H] = 412.3 (MW calc. = 411.16); R = 0.662 mi 1H-NMR (600MHz, DMSOd 6): oe = 1.59 (s, 3H); 2.33 (m, br, 2H); 3.82 (s, 3H); 3.86 (t, J = 6.0 Hz, 2H), 4.12 (m, 2H); 6.78 (s, 1H);7.85 (d, J= 2.4 Hz, 1H), 8.10 (m, 1H), 8.37 (d, J= 2.4 Hz, 1H), 8.59 (s, 2H), 10.32 (s, 1H).

The synthetic route of 56423-63-3 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; NORDHOFF Sonja; OBERBORSCH Stefan; RITTER Stefanie; VOSS Felix; WACHTEN Sebastian; WO2015/197188; A1; (2015);,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

These common heterocyclic compound, 36070-80-1, name is 5-Chloropyrazine-2-carboxylic acid, 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. category: Pyrazines

To a flask fitted with overhead stirrer, condenser, thermometer and nitrogen line was added 5-chloropyrazine-2-carboxylic acid (1.0 eq), DMF (0.069 eq) and toluene (5.52 vols) under a nitrogen atmosphere. The mixture was heated to 60-65 C., and thionyl chloride (1.5 eq) added drop-wise to the batch over approximately 2 hours. The thionyl chloride was washed into the flask with toluene (0.2 vols). The reaction mixture was heated at 60-65 C. for at least 4 hours, then cooled to 40-45 C. and distilled under vacuum, removing approximately 4.5 vol distillates, and distilling to a final volume of 3.2 vols. Toluene (10.6 vol) was added, and the mixture distilled under vacuum at 40-45 C., removing approximately 9.1 vol distillates, and distilling to a final volume of 4.7 vols. The mixture was then cooled to 20-25 C., and dichloromethane (10.6 vols) added. The mixture was cooled to 0-5 C. Meanwhile, to a second flask fitted with overhead stirrer, condenser, thermometer and nitrogen line was added azetidine hydrochloride (0.284 eq), dichloromethane (5.2 vols) under a nitrogen atmosphere. Triethylamine (2.57 eq) was added over at least 15 minutes maintaining the reaction temperature from 20-25 C., the triethylamine was washed into the flask with dichloromethane (0.13 vols), and the mixture cooled to -5 C. to -10 C. The acid chloride solution in the first flask was added to the second flask in portions maintaining the reaction temperature at -5 C. to -10 C. over a time period of 2-5 hours. The pH was tested and adjusted to pH>7 after the acid chloride addition. The reaction mixture was agitated for at least 30 minutes at -5 C. to -10 C. Water (10.6 vols) was added to the second flask and the temperature was allowed to increase to 20-25 C. The mixture was agitated for approximately 25 minutes and then the layers were separated. A 3.17% w/w solution (1.46 eq) of hydrochloric acid (prepared from 32% w/w hydrochloric acid and water) was added to the organic layer B keeping the batch temperature at 20-25 C. The mixture was agitated for 30 minutes at this temperature. The layers were separated, and the organic phase was treated with 26% w/w sodium chloride solution (approximately 8.9 vols) and the batch agitated at 20-25 C. for at least 15 minutes. The layers were separated and the organic layers was heated to reflux, and dichloromethane was removed by atmospheric distillation, distilling to a final volume of approximately 1-2 vols, collecting approximately 11.9 vols distillates. The resulting mixture was cooled to 20-25 C., and heptane (10.5 vols) added. The mixture was heated to reflux for 60 minutes, and then cooled to 90-100 C. The hot solution was filtered through a filter containing 10% w/w of activated charcoal into a clean dry vessel. The filter was washed with heptane (0.43 vols) and the solution cooled to 20-25 C. over at least 2 hours. The resulting crystallised slurry was filtered, and the solid washed with pentane (0.94 vols). After drying in the vacuum oven at 40 C. overnight, the desired product was obtained as a solid (corrected yield 65-78%). 1H NMR delta (400 MHz CDCl3): 2.35-2.42 (2H, m), 4.26 (2H, t), 4.67 (2H, t), 8.52 (1H, d), 9.09 (1H, d); m/z 198 (M+H)+.

The synthetic route of 5-Chloropyrazine-2-carboxylic acid has been constantly updated, and we look forward to future research findings.

Reference:
Patent; AstraZeneca AB; US2010/210841; (2010); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem