Tag: M.W=200-300

Some common heterocyclic compound, 1458-18-0, name is Methyl 3-amino-5,6-dichloropyrazine-2-carboxylate, molecular formula is C6H5Cl2N3O2, 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. 1458-18-0

A. 2-Amino-5,6-dichloro-3-(hydroxymethyl)pyrazine To 70 ml of dry tetrahydrofuran there was added 2-amino-5,6-dichloro-3-(methoxycarbonyl)pyrazine (8.8 g; 0.04M), potassium borohydride (2.7 g; 0.05M), and lithium chloride (2.1 g; 0.05M), and the mixture was stirred at room temperature overnight (17 hours). The reaction mixture was then diluted with about 200 ml of water and chilled, after which the product crystallized, was filtered and dried (5.3 g).

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 1458-18-0, its application will become more common.

Reference:
Patent; Merck & Co., Inc.; US4507299; (1985); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding some certain compound to certain chemical reactions, such as: 63744-22-9, name is 6,8-Dibromoimidazo[1,2-a]pyrazine, can increase the reaction rate and produce products with better performance than those obtained under traditional synthetic methods. Here is a downstream synthesis route of the compound 63744-22-9. 63744-22-9

Intermediate Example 2-1 :Preparation of 6-bromo-8-methylsulfan l-imidazo[1 ,2-a]pyrazineTo a stirred suspension of intermediate example 1 -16,8-dibromo-imidazo[1 ,2-a]pyrazine (489 g, 1766 mmol) in MeOH (2900 mL) at -20 C was dropwise added a solution of sodium methan thiolate (225 g, 3214 mmol, 1 .8 eq) in 800 mL water. After stirring overnight, the clear solution was poured on 30 L water and the yellowish precipitate was filtered, washed with 3 L water and dried in vaccuo to yield 301 g 6-bromo-8-methylsulfanyl-imidazo[1 ,2-a]pyrazine (69.8 %). 1 H-NMR (300 MHz, d6-DMSO): delta = 8.64 (1 H, s), 8.00 (1 H, d), 7.66 (1 H, d2.54 (3H, s) ppm.

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 6,8-Dibromoimidazo[1,2-a]pyrazine.

Reference:
Patent; BAYER PHARMA AKTIENGESELLSCHAFT; KOPPITZ, Marcus; KLAR, Ulrich; JAUTELAT, Rolf; KOSEMUND, Dirk; BOHLMANN, Rolf; BADER, Benjamin; LIENAU, Philip; SIEMEISTER, Gerhard; WO2012/80228; (2012); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

1458-18-0, Name is Methyl 3-amino-5,6-dichloropyrazine-2-carboxylate, 1458-18-0, 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.

The mixture of methyl 3-amino-5, 6-dichloropyrazine-2-carboxylate (4.4 g, 19.91 nMol) , 2- (4-fluorophenyl) -4, 4, 5, 5-tetramethyl-1, 3, 2-dioxaborolane (3.07 g, 21.9 nMol) in dioxane (50 mL) and water (5 mL ) was added Na 2CO 3 (4.22 g, 39.82 nMol) and dppfPdCl 2 (2.84 g, 3.98 nMol) . Then the mixture was stirred at 100 for 1 h under N 2 atmosphere. Then the mixture was concentrated and residue was poured to water (100 mL) and then extracted with EA (100 mL x 3) . The organic solution was then concentrated to afford the crude product (5.5 g, 98%yield) as a yellow solid which was used for next step without further purification. MS m/z (ESI) [M+H] + = 282.2.

Statistics shows that Methyl 3-amino-5,6-dichloropyrazine-2-carboxylate is playing an increasingly important role. we look forward to future research findings about 1458-18-0.

Reference:
Patent; DIZAL (JIANGSU) PHARMACEUTICAL CO., LTD.; QI, Changhe; TSUI, Honchung; ZENG, Qingbei; YANG, Zhenfan; ZHANG, Xiaolin; (399 pag.)WO2020/35052; (2020); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

486424-37-7, A common compound: 486424-37-7, name is 3-Amino-6-bromopyrazine-2-carboxylic acid, belongs to Pyrazines compound, it can change the direction of chemical reaction, and react with certain compounds to generate new functional products. A new synthetic method of this compound is introduced below.

1- (3-DIMETHYLAMINOPROPYL)-3-ETHYLCARBODIIMIDE hydrochloride (0.68 g, 3.5 mmol) was added in one portion to a stirred suspension of 2-MORPHOLIN-4-YLETHANAMINE (0.422 g, 3.2 mmol), 3-amino-6-bromopyrazine-2-carboxylic acid (0.64 g, 3.0 mmol; described in: Ellingson, R. C.; Henry, R. L. J. Am. Chem. Soc. 1949,2798-2800), and 1- hydroxybenzotriazole hydrate (0.48 g, 3.5 mmol) in acetonitrile (25 mL) at 0 C. The cooling bath was removed and stirring was continued at room temperature for 7 h. The solid was filtered off, washed with acetonitrile and purified by column chromatography on silica using methylene CHLORIDE/METHANOL/TRIETHYL amine, (95: 5: 0.1), to give 0.68 g (69% yield) of the title compound : 1H NMR (DMSO-d6, 400 MHz) 8 8.53 (m, 1 H), 8.34 (s, 1 H), 8.68 (br s, 2 H), 3.57 (t, J = 5 Hz, 4 H), 3.37 (q, J = 7 Hz, 2 H), 2.47 (q, J = 7 HZ, 2 I-, 2.40 (m, 4 H); MS (ES) M/Z 330 and 332 (M+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, 3-Amino-6-bromopyrazine-2-carboxylic acid, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; ASTRAZENECA AB; WO2004/55009; (2004); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

6966-01-4, The chemical industry reduces the impact on the environment during synthesis 6966-01-4, name is Methyl 3-amino-6-bromopyrazine-2-carboxylate, I believe this compound will play a more active role in future production and life.

Preparation of methyl 3,6-dibromopyrazine-2-carboxylate A mixture of 3 – amino – 6 – bromopyrazine – 2 – carboxylic acid methyl ester (4 ? 6 2 g ’20 mmol), aqueous hydrobromic acid (48%, 24 ml) and acetic acid (3.2 ml) was added to the reactor, -5 C. The solution (20 ml) of the solution of acetic acid (5 ml) and sodium nitrite (4.8 g, 70 ml) was slowly added successively -5 C stirring reaction lh. The reaction was terminated, washed with saturated sodium sulfite solution, extracted with ethyl acetate and water, washed with saturated NaCl solution and dried over anhydrous sodium sulfate, and the solvent was evaporated under reduced pressure. The residue was purified by silica gel column chromatography to give the title compound as an off-white solid.

The chemical industry reduces the impact on the environment during synthesis Methyl 3-amino-6-bromopyrazine-2-carboxylate. I believe this compound will play a more active role in future production and life.

Reference:
Patent; NANJING SHENGHE PHARMACEUTICAL CO., LTD.; WANG, YONG; ZHAO, LIWEN; LIU, YANG; ZHANG, JINGZHONG; WANG, DEZHONG; GAO, YIPING; CHEN, HONGYAN; ZHANG, CANG; ZHANG, DI; (68 pag.)TWI523856; (2016); B;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

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. 24241-18-7 name is 2-Amino-3,5-dibromopyrazine, 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. 24241-18-7

Preparation of compound 36a: 3,5-dibromopyrazin-2-olTo a stirred solution of 3,5-dibromopyrazin-2-amine (30 g, 0.12 mol) in AcOH (300 ml_) was added dropwise cone. H2SO4 (50 ml_) at 15-25 0C. To the resulting solution was then added dropwise a solution of NaNO2 (16.6 g, 0.24 mol) in water (100 ml_) at 10-15 0C during a period of 1.5 h. After the addition, the resulting mixture was stirred at 10-15 0C for 1 h. The reaction mixture was poured into water (3 L) and extracted with EtOAc (1 L x 3). The combined organic layers were washed with saturated NaHCOs (1 L x 3) and brine (1 L) in sequence, dried over Na2SO4 and concentrated in vacuo which gave the title compound 36a as a yellow solid (24 g, 79.4%). 1H NMR (400 MHz, CDCI3): 7.44 (s, 1 H).

At the same time, in my other blogs, there are other synthetic methods of this type of compound, 2-Amino-3,5-dibromopyrazine, and friends who are interested can also refer to it.

Reference:
Patent; PFIZER INC.; NINKOVIC, Sacha; BRAGANZA, John Frederick; COLLINS, Michael Raymond; KATH, John Charles; LI, Hui; RICHTER, Daniel Tyler; WO2010/16005; (2010); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

5900-13-0, 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. 5900-13-0, name is 5-Bromo-3-methoxypyrazin-2-amine belongs to Pyrazines compound, it is a common compound, a new synthetic route is introduced below.

Synthesis of N-(5 -bromo-3 -methochiypyrazin-2- vDformamide [0207][0208]Acetic anhydride (150 ml) was added dropwise to formic acid (150 ml) under ice- cooling, followed by stirring at the same temperature for 25 minutes. A solution of 5-bromo-3- methoxypyrazin-2-ylamine (CAS No.5900-13-0, 38.7 g) in THF (200 ml) was added dropwise to the reaction mixture over 10 minutes, and then the reaction solution was stirred at room temperature for one hour. Ice water was added to the reaction solution, and the precipitated powder was collected by filtration. The resulting powder was washed with water and then air- dried overnight to obtain 41.2 g of the title compound. The property values of the compound are as follows.1 H-NMR (CDCl3 ) delta (ppm): 4.06 (s, 3H), 7.87 (s, IH), 7.87 (brd, J = 11.0 Hz, IH), 9.37 (d, J =11.0 Hz5 IH).

The synthetic route of 5-Bromo-3-methoxypyrazin-2-amine has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Eisai R&;D Management CO., LTD.; HASEGAWA, Daiju; KITAZAWA, Noritaka; WO2010/98495; (2010); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

24241-18-7, 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. 24241-18-7, name is 2-Amino-3,5-dibromopyrazine, A new synthetic method of this compound is introduced below.

Step 1: Synthesis of 5-Bromo-3-trimethylsilanylethynyl-pyrazm-2-yIamine.[0282] To a solution of 3,5-Dibromo-pyrazin-2-ylamine (3.00 g, 11.86 mmol) in DMF(35 ml) was added triethylamine (16 ml), then tetraldstriphenylphine palladium (0) (685 mg,0.59 mmol) and copper(i) iodide (271 mg, 1.42 mmol) were added sequentially. Finallytrimethylsilylacetylene (2.0 ml, 14.3 mmol) was added dropwise. The reaction mixture wasstirred at 120 C for 30 minutes and then directly adsorbed onto silica gel. Purification byflash chromatography on silica gel with a gradient of ethyl acetate/hexane afforded the titlecompound (2.30g, 71% yield) as yellow oil. MS: m/z 270.0/272.0 [MH+].

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; SGX PHARMACEUTICALS, INC.; WO2006/15124; (2006); A2;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

A common heterocyclic compound, 63744-22-9, name is 6,8-Dibromoimidazo[1,2-a]pyrazine, molecular formula is C6H3Br2N3, 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. 63744-22-9.

General procedure: Method F: compound 6 (2 mmol) was dissolved in MeOH, and stirred at 0 C., to which was added NaSMe (20% aq, 1.8 eq.), followed by naturally warming to room temperature, and reacting overnight, monitored by TCL until complete conversion, to which was added DCM. The system was washed with water, and the organic phase was concentrated to obtain a while solid, which was directly used for the next step reaction.

The synthetic route of 6,8-Dibromoimidazo[1,2-a]pyrazine has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Xiamen University; Deng, Xianming; Huang, Wei; Sun, Xihuan; Zhang, Ting; He, Zhixiang; Liu, Yan; Wu, Xinrui; Zhang, Baoding; Li, Xiaoyang; Zhang, Jingfang; Chen, Yun; Li, Li; Xu, Qingyan; Hu, Zhiyu; (206 pag.)US2020/165246; (2020); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

13301-04-7, The chemical industry reduces the impact on the environment during synthesis 13301-04-7, name is Methyl 3,6-dibromopyrazine-2-carboxylate, I believe this compound will play a more active role in future production and life.

To a solution of methyl 3,6-dibromopyrazine-2-carboxylate (583 mg, 1.97 mmol), and (2,3-dichlorophenyl)boronic acid (375 mg, 1.97 mmol) in dioxane (40 ml) was added CS2CO3 (1.93 g, 5.91 mmol) in H2O (10 mL) and PdCkdppf (144 mg, 0.2 mmol). The reaction was refluxed for 20 min, allowed to cool to rt, and extracted with EtOAc. The combined organic layers were washed with brine and dried over MgS04. The mixture was concentrated under reduced pressure. Purification by flash chromatography resulted in 370 mg (52%) of the desired product. NMR (500 MHz, CDCh) delta 8.58 – 8.53 (m, 1H), 7.38 – 7.32 (m, 1H), 7.29 – 7.22 (m, 1H), 7.14 – 7.08 (m, 1H), 3.82 – 3.76 (m, 3H).

The chemical industry reduces the impact on the environment during synthesis Methyl 3,6-dibromopyrazine-2-carboxylate. I believe this compound will play a more active role in future production and life.

Reference:
Patent; REVOLUTION MEDICINES, INC.; LI, Jie Jack; KOLTUN, Elena S.; GILL, Adrian Liam; BUCKL, Andreas; WON, Walter; AAY, Naing; MELLEM, Kevin; TZITZILONIS, Christos; JOGALEKAR, Ashutosh; CREGG, James Joseph; (177 pag.)WO2019/75265; (2019); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem