Tag: M.W=100-200

These common heterocyclic compound, 56423-63-3, name is 2-Bromopyrazine, 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. Formula: C4H3BrN2

Example 50 N-(4-trifluoromethylphenyl)-3-(4-chlorophenyl)-4-methyl-4-(pyrid-2-ylamino)-4,5-dihydro-1H-pyrazole-1-carboxamide To 2.0 g (5.0 mmole) of N-(4-trifluoromethylphenyl)-3-(4-chlorophenyl)-4-methyl-4-amino-4,5-dihydro-1H-pyrazole-1-carboxamide (Example 3) in 4 g of dimethylformamide was added 1.0 g (6.5 mmole) of 2-bromopyridine. The mixture was refluxed for 2 hours and then cooled. Partitioning between diethyl ether and dilute aqueous sodium bicarbonate, washing with brine, drying over anhydrous magnesium sulfate, and chromatography over silica gel using diethyl ether and hexanes yielded 0.2 g of Example 50, a white solid. mp 130-140 C. Example 51 was prepared following substantially the same procedure and substituting bromopyrazine for 2-bromopyridine.

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

Reference:
Patent; Rohm and Haas Company; US5798311; (1998); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 56423-63-3, A common heterocyclic compound, 56423-63-3, name is 2-Bromopyrazine, molecular formula is C4H3BrN2, 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 above oily liquid was dissolved in 10 mL of ethylene glycol dimethyl ether and 2 mL of water, and 2-bromopyrazine (129 mg, 0.81 mmol), Pd(PPh3)4 (24 mg, 0.020 mmol) and Na2CO3 (215 mg, 2.03 mmol) were stirred at 100 C for 2 hours under nitrogen atmosphere. After cooling to room temperature, the reaction solution was poured into 60 mL of water and extracted three times with 20 mL of ethyl acetate. The combined ethyl acetate was washed with brine and dried over anhydrous sodium sulfate. Filtered, and concentrated by column chromatography (petroleum ether / ethyl acetate 1/1) to give 36mg as a white solid powder that is Compound A-2.

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

Reference:
Patent; Shenzhen Tajirui Bio-pharmaceutical Co., Ltd.; Wang Yihan; Zhao Jiuyang; (35 pag.)CN109651359; (2019); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 1320266-90-7, 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. 1320266-90-7, name is 8-Chloro-3-isopropylimidazo[1,5-a]pyrazine belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below.

Intermediate J (33 mg, 0.17 mmol) dissolved in 0.18 mL of DMF was added to NIS (39 mg, 0.17 mmol) dissolved in 0.6 mL of DMF. The reaction mixture was heated to 60 C for 3 h and then cooled to room temperature. The reaction mixture was partitioned between 1 M a2S03 and dichloromethane. The aqueous layer was then extracted with dichloromethane (3X). The organic layers were combined, dried over a2S04 and concentrated in vacuo to afford 34 mg (62% yield) of pure Intermediate K. .H-NMR (300 MHz, CDC13) delta 1.41 (d, 6H, / = 6.9 Hz), 3.20-3.31 (m, 1H), 7.28 (d, 1H, J= 5.1 Hz), 7.65 (d, 1H, J = 5.1 Hz). MS (ESI) (M+H)+ 322.1.

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, 8-Chloro-3-isopropylimidazo[1,5-a]pyrazine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; UNIVERSITY OF WASHINGTON; VAN VOORHIS, Wesley, C.; HOL, Wilhelmus, G.J.; LARSON, Eric, T.; MALY, Dustin, James; MERRITT, Ethan; OJO, Kayode, K.; WO2011/94628; (2011); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 939412-86-9, A common heterocyclic compound, 939412-86-9, name is (3-Chloropyrazin-2-yl)methanamine hydrochloride, molecular formula is C5H7Cl2N3, 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.

Intermediate 12. Step 12: N-((3-chloropyrazin-2-yl)methyl)-2.3.3-trimethyl-l-oxooctahvdro-lH-pyrido[1.2- clpyrimidine-7-carboxamide (trans) To a solution of 2,3,3-trimethyl-l -oxooctahydro-lH-pyrido[l ,2-c]pyrirnidine-7-carboxylic acid (560 mg, 2.330 mmol) in DMF (25 mL) was added HATU (1329 mg, 3.50 mmol), the mixture was stirred at 20 C for 0.5 h. Then (3-chloropyrazin-2-yl)methanamine,HCl (503 mg, 2.80 mmol) was added, followed by Epsilon Nu (1.299 mL, 9.32 mmol). The mixture was stirred at 20 C – I l l – for 18 h. TLC showed the material was consumed completely, then the reaction mixture was poured into water (20 mL), extracted with DCM (20 mLx2). The organic layer was washed with brine (40 mL), dried over Na2SC>4, concentrated in vacuo to give N-((3-chloropyrazin-2- yl)methyl)-2,3,34rimethyl-l-oxooctahydro-lH-pyrido[l,2-c]pyrirnidine-7-carboxamide (trans) . XH NMR (400MHz, CD3OD) delta 8.52 (d, J = 2.3 Hz, 1H), 8.33 (s, 1H), 4.62 (s, 2H), 4.56 (d, J = 12.9 Hz, 1H), 3.26 – 3.21 (m, 1H), 2.86 (s, 3H), 2.65 (t, J= 12.3 Hz, 1H), 2.43 (t, J= 11.7 Hz, 1H), 2.03 – 1.82 (m, 4H), 1.67 (br. s., 1H), 1.31 (s, 3H), 1.29 – 1.24 (m, 1H), 1.21 (s, 3H) ppm.

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; MERCK SHARP & DOHME CORP.; LIU, Jian; KOZLOWSKI, Joseph, A.; ALHASSAN, Abdul-Basit; BOGA, Sobhana Babu; GAO, Xiaolei; GUIADEEN, Deodialsingh; WANG, Jyhshing; XU, Jiayi; YU, Wensheng; YU, Younong; CAI, Jiaqiang; LIU, Shilan; WANG, Dahai; WU, Hao; YANG, Chundao; (211 pag.)WO2016/109221; (2016); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

32111-28-7, name is N-Methylpyrazin-2-amine, 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. COA of Formula: C5H7N3

In a 100 mL two-neck flask, 2-methylaminopyrazine (114 muL, 1.2 mmol), N-(3-bromo-5-methoxyphenyl)-benzamide (244 mg, 0.8 mmol) were added,Potassium phosphate (339 mg, 1.6 mmol), copper iodide (15 mg) and anhydrous DMSO (15 mL) were reacted overnight at 110C under argon atmosphere.After the reaction solution was cooled, 15 mL of water was added and the mixture was extracted with ethyl acetate (15 mL×2), and the solvent was removed under reduced pressure.The residue was purified by silica gel chromatography (petroleum ether/ethyl acetate gradient) to give N-(3-methoxy-5-(methyl-2-pyrazinylamino)phenyl)-benzamide 122 mg The yield is 50%.

The synthetic route of 32111-28-7 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Sun Yat-sen University; Chinese Academy Of Sciences Guangzhou Bio-pharmaceutical And Health Institute; Yan Ming; Zhang Tianyu; Zhang Niuniu; Liu Zhiyong; Qian Lu; Tang Yunxiang; Cheng Yajuan; Zhang Xuejing; (25 pag.)CN107973727; (2018); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

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. category: Pyrazines

EXAMPLE 41B 5-Bromo-2-iodopyrazine Under N2, to the mixture of the product of Example 41A (7.50 g, 43 mmol) in DME (anhydrous, Aldrich, 200 mL) was added CsI (Aldrich, 11.20 g, 43 mmol), iodine (Aldrich, 5.52 g, 21.6 mmol), CuI (Stream, 2.52 g, 13.2 mmol) and isoamyl nitrite (34.8 mL, 259.2 mmol) at ambient temperature. It was then heated to 60 C. and stirred for 30 min. till no gas evolution was observed. After being cooled down to room temperature, the dark mixtures was poured into a flask containing EtOAc (200 mL) and saturated NH4Cl (200 mL), stirred for 10 min. The organic layer was separated and the aqueous layer was extracted with EtOAc (2*1000 mL). The combined organic solution was washed with 5% of Na2S2O3 aqueous (2*50 mL), brine (50 mL) and dried over MgSO4. The drying agents were filtered off and the organic solution was concentrated to provide the title compound. 1H NMR (300 MHz, CDCl3) delta 8.50 (d, J=1.36 Hz, 1H), 8.62 (d, J=1.36 Hz, 1H) ppm; m/z 284 (M+H)+, 286 (M+H)+.

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

Reference:
Patent; Ji, Jianguo; Li, Tao; Lynch, Christopher L.; Gopalakrishnan, Murali; US2008/45539; (2008); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 4774-14-5, 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. 4774-14-5, name is 2,6-Dichloropyrazine belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below.

110 mL of THF was added to 2,2,6,6-tetramethylpiperidine (3.3 mL, 20 mmol) and cooled to -78C. n-BuLi (2.5M hexane solution, 8 mL, 20 mmol) was added thereto, and the mixture was stirred at -78C for 30 minutes. 2,6-Dichloropyrazine (2.0 g, 13.4 mmol) dissolved in 20 mL was added thereto, and the mixture was stirred at -78C for90minutes. Iodomethane (3.8 mL, 60 mmol) was added thereto, and the mixture was stirred at room temperature for 3hours. Solids were removed by filtration, and the filtrate was purified by column chromatography to obtain the titlecompound (0.77 g, 35 %).1H-NMR (CDCl3) delta 8.41 (1H, s), 2.65 (3H, s)

The synthetic route of 2,6-Dichloropyrazine has been constantly updated, and we look forward to future research findings.

Reference:
Patent; LG Chem, Ltd.; KIM, Young Kwan; PARK, Sang Yun; JOO, Hyun Woo; CHOI, Eun Sil; PAEK, Seung Yup; KANG, Seung Wan; KIM, Byung Gyu; LEE, Chang Seok; KIM, Sung Wook; LEE, Sang Dae; (369 pag.)EP3239143; (2017); A2;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 4430-75-5,Some common heterocyclic compound, 4430-75-5, name is Octahydro-2H-pyrido[1,2-a]pyrazine, molecular formula is C8H16N2, 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.

DIPEA (71 mg, 00.1 mL, 0.55 mmol) was added to a stirred solution of (R)-5-(2-(2,5-difluorophenyl)pyrrolidin-1-yl)pyrazolo[1,5-a]pyridine-3-carboxylic acid (75 mg, 0.22 mmol) in DMF (1.5 mL) followed by addition of EDCl (63 mg, 0.33 mmol) and HOBt (32 mg, 0.24 mmol). After 10 minutes of stirring the reaction mixture, octahydro-1H-pyrido[1,2-a]pyrazine (46 mg, 0.33 mmol) was added and the resulting mixture was stirred for 16 h at 20-35 C. The reaction mixture was diluted with cold water and extracted with ethyl acetate. The ethyl acetate layer was washed with water and brine solution. The ethyl acetate portion was dried over anhydrous sodium sulfate and concentrated under reduced pressure to afford the crude compound, which was refluxed in hexane, filtered, and the filtrate was concentrated under reduced pressure to afford 45 mg of the title compound as a yellow solid. MS (ESI): m/z 466.3 (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 Octahydro-2H-pyrido[1,2-a]pyrazine, its application will become more common.

Reference:
Patent; DR. REDDY’S LABORATORIES LTD.; Sasmal, Pradip Kumar; Ahmed, Shahadat; Prabhu, Ganesh; Tehim, Ashok; Paradkar, Vidyadhar; Dattatreya, Marahanakuli Prasanna; Mavinahalli, Nanjegowda Jagadeesh; US2015/5280; (2015); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 5521-55-1, As we all know, there are many different methods for the synthesis of a compound, and people can choose the synthesis method that suits their own laboratory according to the actual situation. 5521-55-1 name is 5-Methylpyrazine-2-carboxylic acid, This compound is widely used in many fields, so it is necessary to find a new synthetic route. The downstream synthesis method of this compound is introduced below.

General procedure: To a solution of R1COOH (1mmol) in DMF (5ml), DIEA (3mmol), intermediate 3 (1.1mmol) and HBTU (1mmol) were added at room temperature for 10h. The mixture was diluted with 20ml water and extracted with ethyl acetate (3×20ml). The combined organic layers were washed with saturated aqueous sodium bicarbonate and brine, and then dried over anhydrous sodium sulfate. After removing the solvent under reduced pressure, the crude product was purified by flash chromatography on silica gel, eluting with dichloromethane/methanol (2-5%), yield 70-95%.

At the same time, in my other blogs, there are other synthetic methods of this type of compound, 5-Methylpyrazine-2-carboxylic acid, and friends who are interested can also refer to it.

Reference:
Article; Yao, Dahong; Zhou, Yuxin; Zhu, Lingjuan; Ouyang, Liang; Zhang, Jin; Jiang, Yingnan; Zhao, Yuqian; Sun, Dejuan; Yang, Shilin; Yu, Yang; Wang, Jinhui; European Journal of Medicinal Chemistry; vol. 140; (2017); p. 155 – 171;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route 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.

EXAMPLE 157A Methyl 3-bromopyrazine-2-carboxylate To a rapidly stirring heterogeneous mixture of 3-aminopyrazine-2-carboxylic acid methyl ester (2.00 g, 13.1 mmol) in 48% hydrobromic acid (7.9 mL) cooled to 0 C. was added bromine (2.00 mL, 6.2 g, 38.8 mmol) dropwise over 5 minutes. Then a solution of sodium nitrite (2.27 g, 32.8 mmol) in 9.5 mL of water was added dropwise over 10 minutes. The reaction mixture was stirred at 0 C. for 15-30 minutes and then basified with 60 mL of saturated sodium bicarbonate solution and extracted with ethyl acetate followed by chloroform. The combined organic extracts were dried over magnesium sulfate and concentrated under reduced pressure. The residue obtained was flash chromatographed on silica gel eluding with mixtures of hexane and ethyl acetate to afford the title compound (1.265 g, 46%). m.p. 43.5-44 C. 1 H NMR (CDCl3, 300 MHz) delta 4.04 (s, 3H), 8.50 (bs, 1H), 8.60 (bs, 1H). MS (DCl/NH3) m/e 217/219 (M+H)+, 234/236 (M+H+NH3)+.

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:
Patent; Abbott Laboratories; US5250548; (1993); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem