Month: September 2021

59489-71-3, name is 2-Amino-5-bromopyrazine, 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. Quality Control of 2-Amino-5-bromopyrazine

A mixture of 2-amino-5-bromopyrazine (0.5 g, 2.79 mmol) and [4-(methylsulfonyl)phenyl]boronic acid (0.57 g, 2.79 mmol) in 1,4-dioxane (10 mL) and MeOH (4 mL) was treated with 2M Na2CO3 (4 mL) and Pd(PPh3)4 (65 mg, 0.06 mmol). The reaction mixture was degassed with N2 and heated at 100 C. for 3 h. Most of 1,4-dioxane and MeOH was removed under reduced pressure. Water was added, and the mixture was extracted with EtOAc (50 mL×4). The combined organic extracts were washed with brine, dried over Na2SO4, filtered, and the filtrate was concentrated to a brown solid, which was triturated with CH2Cl2 to give 0.465 g (67%) of 5-[4-(methylsulfonyl)phenyl]-2-pyrazinamine as a yellow solid. The filtrate was washed with 1 N HCl (25 mL), and the aqueous layer was separated and basified with 4N NaOH. The mixture was extracted with EtOAc (50 mL×2) and the combined organic extracts were washed with brine, dried over Na2SO4, filtered, and the filtrate was concentrated to give additional 0.045 g (7%) of 5-[4-(methylsulfonyl)phenyl]-2-pyrazinamine as a yellow solid. 1H NMR (400 MHz, DMSO-d6): delta 8.63 (s, 1H), 8.15 (d, 2H, J=8.5 Hz), 7.97 (s, 1H), 7.91 (d, 2H, J=8.5 Hz), 6.81 (s, 2H), 3.20 (s, 3H); LRMS (ESI), m/z 250 (M+H).

The synthetic route of 59489-71-3 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; SMITH KLINE BEECHAM CORPORATION a corporation; US2010/29650; (2010); 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. 22047-25-2, name is Acetylpyrazine, A new synthetic method of this compound is introduced below., Formula: C6H6N2O

General procedure: To a stirred solution of aldehyde (10mmol) (4-(dimethylamino)benzaldehyde, 4-(1-piperidinyl)benzaldehyde, 4-(4-morpholinyl)benzaldehyde or 4-(diphenylamino)benz-aldehyde) in EtOH (75mL), ketone (20mmol) (2-acetylpyridine, 2-acetylthiazole or 2-acetylpyrazine) was added. Then KOH (1.54g, 27.5mmol) and NH3 (aq) (35mL) were added to the reaction mixture. The solution was stirred at room temperature for 24h. The solid was collected by filtration and washed with H2O. Recrystallization from ethanol (1, 4, 7, 10) or toluene (2, 3, 5, 6, 8, 9, 11, 12) afforded a crystalline solid.

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:
Article; Palion-Gazda, Joanna; Machura, Barbara; Klemens, Tomasz; Szlapa-Kula, Agata; Krompiec, Stanis?aw; Siwy, Mariola; Janeczek, Henryk; Schab-Balcerzak, Ewa; Grzelak, Justyna; Ma?kowski, Sebastian; Dyes and Pigments; vol. 166; (2019); p. 283 – 300;,
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. 13924-95-3, name is Methyl 5-hydroxypyrazine-2-carboxylate, A new synthetic method of this compound is introduced below., COA of Formula: C6H6N2O3

Potassium carbonate (8.82 g) and sodium chlorodifluoroacetate (6.53 g) were added to a solution of methyl 5-hydroxypyrazine-2-carboxylate (3.3 g) in DMF (42.8 ml). The reaction solution was stirred at 100 C. for 30 minutes, and then saturated aqueous ammonium chloride was added, followed by extraction with ethyl acetate. The organic layer was washed with a saturated sodium bicarbonate solution and brine and then dried over magnesium sulfate. The drying agent was removed by filtration and then the solvent was evaporated under reduced pressure. The residue was purified by silica gel column chromatography to obtain the title compound (928 mg).1H-NMR (400 MHz, CDCl3) delta (ppm): 4.04 (s, 3H), 7.49 (t, J=71.2 Hz, 1H), 8.47 (d, J=0.8 Hz, 1H), 8.92 (d, J=0.8 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; EISAI R&D MANAGEMENT CO., LTD.; US2010/93999; (2010); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 14667-55-1, A common heterocyclic compound, 14667-55-1, name is 2,3,5-Trimethylpyrazine, molecular formula is C7H10N2, 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.

EXAMPLE IV Preparation Of 1-(2,3,5-Trimethyl-6-pyrazinyl)-1-propanone STR8 The reaction of trimethylpyrazine and freshly distilled propionaldehyde is carried out as described in Example I on the same molar scale. Preparative thick layer chromatography (2000mu silica gel GF, developed in 5% acetone/hexane) of the crude reaction product gives a 48% yield of 1-(2,3,5-trimethyl-6-pyrazinyl)-1-propanone (mp 65-67 C.). An analytically pure sample for odor and flavor evaluation is obtained by preparative GLC (1/4″*15′ Carbowax 20M-TPA). The structure is verified by spectroscopy. Anal. calc. for C10 H14 N2 O: C, 67.39; H, 7.92; N, 15.72; Found: C, 67.24; H, 8.13; N, 15.62.

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; Philip Morris Incorporated; US4588813; (1986); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

These common heterocyclic compound, 486424-37-7, name is 3-Amino-6-bromopyrazine-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. name: 3-Amino-6-bromopyrazine-2-carboxylic acid

Step 1. Synthesis of tert-butyl (l-(2-(3-amino-6-bromopyrazine-2-carboxamido) pyridin- 3 -y l)piperidin-4-yl)carbamate In a 100 mL round-bottom flask equipped with a magnetic stirrer, a solution of 3-amino- 6-bromopyrazine-2-carboxylic acid (1.044 g, 4.79 mmol), tert- butyl (l-(2-aminopyridin-3- yl)piperidin-4-yl)carbamate (1.4 g, 4.79 mmol), DIPEA (2.091 mL, 11.97 mmol) and HATU (2.185 g, 5.75 mmol) in DMF (15 mL) was stirred at 25 C for 15 hr. The reaction mixture was quenched with 30 mL water and extracted with EtOAc (3 X 20 mL). The ethyl acetate wash was dried over Na2S04 and concentrated. The crude product was purified by silica gel chromatography using ethyl acetate and heptane which gave 3-amino-N-(3-(4-aminopiperidin-l- yl)pyridin-2-yl)-6-bromopyrazine-2-carboxamide (1.76 g, 3.57 mmol) in 74 % yield. LC-MS (acidic method): : ret.time= 1.17 min, M+H = 492.3.

The synthetic route of 3-Amino-6-bromopyrazine-2-carboxylic acid has been constantly updated, and we look forward to future research findings.

Reference:
Patent; NOVARTIS AG; LUZZIO, Michael Joseph; PAPILLON, Julien; VISSER, Michael Scott; (213 pag.)WO2016/20864; (2016); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 33332-25-1, A common heterocyclic compound, 33332-25-1, name is Methyl 5-chloropyrazine-2-carboxylate, molecular formula is C6H5ClN2O2, 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.

863 mg of 5-chloropyrazine-2-carboxylic acid methyl ester was dissolved in 13 ml of N, N-dimethylformamide, 0.67 ml of 1-methylpiperazine and 5 ml of N, N-diisopropylethyl The mixture was heated to 80 C under argon, and the mixture was heated for 2 hours. After heating, the reaction solution was diluted with 65 ml of water and extracted with ethyl acetate. The organic phases were combined and washed with saturated aqueous sodium chloride solution five times, Dried over sodium, filtered and concentrated, and the residue was subjected to column chromatography (dichloromethane: methanol = 99: 1-97: 3, v / v) to give 1.024 g of a yellowish solid in 86.7% yield.

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

Reference:
Patent; Chinese Academy Of Sciences Shanghai Pharmaceutical Institute; Duan Wenhu; Geng Meiyu; Zhao Bin; Ding Jian; Ai Jing; Fan Jun; Peng Xia; Yan Wei; Chen Yi; (77 pag.)CN106146493; (2016); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 768-05-8,Some common heterocyclic compound, 768-05-8, name is Pyrazinoic acid hydrazide, molecular formula is C5H6N4O, 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.

General procedure: To a stirred solution of the acid hydrazide 5 (2mmol, 0.27g) in absolute ethanol (10ml), the appropriate heteroaromatic ketone or substituted pyrazolaldehyde (2mmol) was added in the presence of catalytic amount of glacial acetic acid (5 drops), the mixture was refluxed for 12-16h. The product obtained was filtered, washed with diethyl ether, dried and recrystallized from ethanol.

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route Pyrazinoic acid hydrazide, its application will become more common.

Reference:
Article; Hassan, Nayera W.; Saudi, Manal N.; Abdel-Ghany, Yasser S.; Ismail, Azza; Elzahhar, Perihan A.; Sriram, Dharmarajan; Nassra, Rasha; Abdel-Aziz, Marwa M.; El-Hawash, Soad A.; Bioorganic Chemistry; vol. 96; (2020);,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 5049-61-6, A common heterocyclic compound, 5049-61-6, name is Pyrazin-2-amine, molecular formula is C4H5N3, 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 solution of dichloromethane (200 mL) and pyridine (25.3 mL, 0.315 mol) was added to a three-necked flask containing 2-aminopyrazine (14.27 g, 0.15 mol) and stirred well. In the dark and while refluxing a solution of bromine (16.2 mL, 0.315 mol) in dichloromethane (100 mL) was slowly added dropwise to the three-necked flask. About 1 h later the addition finished and the mixture was refluxed at 40 C for 30 min more. After TLC monitoring indicated the reaction was complete, the reaction mixture was cooled to room temperature and distilled water (50 mL) was added and themixture was stirred vigorously for 10 min. Then the organic layer was collected and washed twice with distilled water. Silica gel (10 g) and activated carbon (1 g) were added to the organic layer and the mixture was decolorized under reflux for 30 min. After hot filtration, the filtrate was collected and vacuum distilled. The residue was refluxed with n-hexane (45 mL) for 2 h, filtered while hot again and the solid product was dried and weighed to give 18.15 g of a pale yellow solid (47.8% yield). 1H-NMR(DMSO-d6) delta 8.14 (s, 1H), 7.01 (s, 2H).

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

Reference:
Article; Xu, Shan; Sun, Chengyu; Chen, Chen; Zheng, Pengwu; Zhou, Yong; Zhou, Hongying; Zhu, Wufu; Molecules; vol. 22; 2; (2017);,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature 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.

A mixture of 2-bromo-5-chloro-pyrazine (2 g, 10.34 mmol), 3-fluoro-5-(4,4,5,5-tetramethyl-l,3,2-dioxaborolan-2-yl)-2-(2,2,2-trifluoro-l,l- dimethyl-ethoxy)pyridine (3.61 g, 10.34 mmol), CS2CO3 (6.74 g, 20.68 mmol) andPd(dppf)Cl2 (1.13 g, 1.55 mmol) in l,4-Dioxane (80 mL) and Water (8 mL) was stirred at 55 C under N2 for 5 hours. The mixture was cooled to room temperature and concentrated to give a residue. To the residue was added water (50 mL) and extracted with EtOAc (50 mL x 2). The combined organic phase was washed with water (50 mL), brine (50 mL x 2), dried over anhydrous Na2S04, filtered and concentrated to give the crude product. The crude product was purified by flash chromatography column on silica gel (EtOAc in PE = 0% to 5% to 10%) to give the product (2.3 g, 5.45 mmol) as a solid. ‘H NMR (400 MHz, CDCI3) dH= 8.77 (d, 1H), 8.64 (d, 1H), 8.53 (d, 1H), 8.05 (dd, 1H), 1.88 (s, 6H). LCMS R, = 0.96 min in 1.5 min chromatography, MS ESI calcd. for Ci3HnClF4N30 [M+H]+336.0, found 335.9.

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; PRAXIS PRECISION MEDICINES, INC.; GRIFFIN, Andrew, Mark; MARRON, Brian, Edward; MARTINEZ BOTELLA, Gabriel; REDDY, Kiran; WITTMANN, Marion; (0 pag.)WO2019/232209; (2019); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 143591-61-1, 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. 143591-61-1, name is 3-Bromo-8-chloroimidazo[1,2-a]pyrazine belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below.

To a solution of 3-bromo-8-chloro-imidazo[l,2-a]pyrazine (4.0 g, 18.2 mmol) in DMF (16 ml.) MeSNa (1.52 g, 21.8 mmol) is added and stirred at 70 0C for 2h. After this time the solution is allowed to cool, poured into 16ml_ of water, stirred for 30 minutes and the solid obtained filtered off and washed with water (3 x 5OmL). The product, 3-Bromo-8-methylsulfanyl- imidazo[l,2-a]pyrazine was obtained as a beige solid (3.21 g, 72.3 %).

The synthetic route of 3-Bromo-8-chloroimidazo[1,2-a]pyrazine has been constantly updated, and we look forward to future research findings.

Reference:
Patent; BIOFOCUS DPI LIMITED; WO2009/24585; (2009); A2;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem