Month: August 2021

Synthetic Route of 16298-03-6, These common heterocyclic compound, 16298-03-6, name is Methyl 2-aminopyrazine-3-carboxylate, 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.

General procedure: Used for N-benzyl derivatives 1-8. The starting 3-aminopyrazine-2-carboxylic acid(Sigma-Aldrich, Schnelldorf, Germany; 2.2 g; 15.8 mmol) in methanol (250 mL) was cooled downto 0 C and concentrated H2SO4 (3.2 mL) was added. The reaction mixture was stirred for 48 h atrt. Subsequently the reaction mixture was poured into water (27 mL) and alkalized by NaHCO3(approx. 6.3 g) to pH = 7. The precipitate was filtered off and collected as white-brown solid toobtain methyl 3-aminopryzine-2-carboxylate [32]. Methyl 3-aminopyrazine-2-carboxylate (100 mg;0.65 mmol) in methanol (2 mL) along with substituted benzylamine (1.95 mmol; 3 equiv) and NH4Cl(10 mg; 0.19 mmol; 0.1 equiv) [33] were put into reaction tube used for microwave assisted synthesiswith a magnetic stirrer. Reaction was performed in a CEM Discover microwave reactor with a focusedfield in pressurized vials with the following settings: 130 C, 90 W and 40 min. The progress of thereaction was checked using TLC (Merck Silica 60 F254) developed by in hexane/ethyl-acetate 2:1 system.The reaction mixture was adsorbed to silica gel and purified by flash chromatography (Teledyne IscoInc.,) using silica (irregular, 40-63 m) as a stationary phase and gradient elution EtOAc in hexane0-100%, with respect to the expected lipophilicity of the product.

Statistics shows that Methyl 2-aminopyrazine-3-carboxylate is playing an increasingly important role. we look forward to future research findings about 16298-03-6.

Reference:
Article; Bouz, Ghada; Semelkova, Lucia; Jand?ourek, Ond?ej; Kone?na, Klara; Paterova, Pavla; Navratilova, Lucie; Kubi?ek, Vladimir; Kune?, Ji?i; Dole?al, Martin; Zitko, Jan; Molecules; vol. 24; 7; (2019);,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 71257-38-0, 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. 71257-38-0 name is 1,2,3,4-Tetrahydropyrrolo[1,2-a]pyrazine, 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.

Example 1112,2-Dimethyl-1 -(7-(phenylethynyl)-3,4-dihydropyrrolo[1,2-a]pyrazin-2(1H)- yl)propan-1-one[00350] Pivaloyl chloride (3.27 g, 3.34 mL, 27.2 mmol) is added dropwise at 0 C to a solution of 1 ,2,3,4-tetrahydropyrrolo[1 ,2-a]pyrazine (3.01 g, 24.7 mmol) (WO2009/90055) and TEA (4.60 mL, 32.6 mmol) in DCM (40 mL). The resulting mixture is stirred at 0 C for 15 min and washed with an aqueous citric acid solution (10%). The organic phase is dried over MgSO and concentrated at reduced pressure. The obtained residue is purified by column chromatography (silica gel, DCM/acetone, 10:1 ) to give 1 -(3,4-dihydropyrrolo[1 ,2-a]pyrazin-2(1 H)-yl)-2,2-dimethylpropan-1 -one (3.10 g, 61 %) as a yellowish crystalline intermediate product.

At the same time, in my other blogs, there are other synthetic methods of this type of compound, 1,2,3,4-Tetrahydropyrrolo[1,2-a]pyrazine, and friends who are interested can also refer to it.

Reference:
Patent; MERZ PHARMA GmbH & CO. KGaA; ZEMRIBO, Ronalds; FOTINS, Juris; ABEL, Ulrich; KUBAS, Holger; MEYER, Udo; WOLTER, Falko Ernst; HECHENBERGER, Mirko; WO2012/172093; (2012); 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. 330786-09-9, name is Methyl 3,5-dichloropyrazine-2-carboxylate, A new synthetic method of this compound is introduced below., Product Details of 330786-09-9

Methyl 3,5-dichloropyrazine-2-carboxylate (5.0 g, 24.2 mmol) was dissolved in a 9: 1 mixture of dry tetrahydrofuran (242 mL) and methanol (27 mL). The mixture was cooled to 1.5-2 C with an ice/water bath and stirred at this temperature for 10 min. A 2 M solution of lithium borohydride in THF (13.3 mL, 26.6 mmol) was then added carefully keeping the temperature below 4-5 C. After addition, the reaction mixture was stirred for an additional 10-15 min at 0-4 C. Methanol (120 mL) was added to the flask and the mixture stirred for 15 min at rt. The reaction was slowly poured into a mixture of 1 M HC1 solution (100 mL) and ethyl acetate (200 mL). The resulting mixture was stirred at rt for 15 min. The aqueous layer was extracted with ethyl acetate (3 x 150 mL) and the combined organics washed with brine (2 x 100 mL), dried over anhydrous MgS04, filtered, and concentrated under reduced pressure. (3,5-Dichloropyrazin-2-yl)methanol (4.3 g, 99% yield) was obtained as a yellow oil after drying under high vacuum for 2 h. 1H-NMR (500 MHz, CDCI3) d 8.52 (s, 1H), 4.85 (s, 2H).

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; RELAY THERAPEUTICS, INC.; D.E. SHAW RESEARCH, LLC; TAYLOR, Alexander, M.; LESCARBEAU, Andre; KELLEY, Elizabeth, H.; SHORTSLEEVES, Kelley, C.; WALTERS, W., Patrick; MURCKO, Mark, Andrew; MCLEAN, Thomas, H.; GUNAYDIN, Hakan; GIORDANETTO, Fabrizio; THERRIEN, Eric; (607 pag.)WO2019/183367; (2019); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Each compound has different characteristics, and only by selecting the characteristics of the compound suitable for a specific situation can the compound be applied on a large scale. 1320266-90-7, name is 8-Chloro-3-isopropylimidazo[1,5-a]pyrazine, This compound has unique chemical properties. The synthetic route is as follows., SDS of cas: 1320266-90-7

To a solution of 8-chloro-3-isopropylimidazo[1,5-ajpyrazine 3A (1.00 g, 5.11 mmol) in THFat -65 C was added dropwise a solution of n-butyllithium (2.5 M solution in THF, 2.9 mL,7.16 mmol), keeping the temperature below -55 C. The resulting dark brown solution was stirred at -78 C for 1 h then ethyl formate (0.62 mL, 7.67 mmol) was added dropwise and the mixture was stirred at -78 C for 1.5 h. The mixture was diluted with water and extracted with EtOAc. The combined organic extracts were dried (MgSO4), filtered and concentrated invacuo. The residue was purified by silica-gel chromatography, eluting with 0-50% EtOAc in isohexane to give the title compound 3B as a yellow oil that crystallised on standing (900 mg, 79%). LC-MS (Method 1): Rt = 1.06 mm, m/z = 224.1 [M(35C1)+Hf?.

According to the analysis of related databases, 1320266-90-7, the application of this compound in the production field has become more and more popular.

Reference:
Patent; OPTIKIRA LLC; THE REGENTS OF THE UNIVERSITY OF CALIFORNIA; KEENAN, Richard M.; BACKES, Bradley J.; MALY, Dustin J.; REYNOLDS, Charles; WHITTAKER, Ben; KNIGHT, Jamie; SUTTON, Jon; HYND, George; PAPA, Feroz, R.; OAKES, Scott, A.; (147 pag.)WO2019/46711; (2019); 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. 89123-58-0, name is 5-Bromopyrazine-2,3-diamine, A new synthetic method of this compound is introduced below., Recommanded Product: 89123-58-0

The compound 5-bromo-2,3-diaminopyrazine 1b (12.0 g, 63.8 mmol) was added to triethyl orthoformate (94.4 g, 638 mmol), and the reaction mixture was reacted at 145 C overnight. Complete the reaction monitored by TLC, cooled and concentrated by column (v / v, dichloromethane / methanol = 100: 1-30: 1) to give the title compound 1c (10.0g, 50.5mmol), in a yield of 79.4%

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; Shanghai Huahuituo Pharmaceutical Technology Co., Ltd.; Zhejiang Huahai Pharmaceutical Co., Ltd.; Xu Xin; Zhang Tian; Li Yunfei; Wang Guan; Zhu Weibo; Li Qiang; Qu Minkai; Zhang Linli; Song Jinqian; Liu Lei; Chen Haiji; Liu Qiang; Wang Yijin; Ge Jian; (67 pag.)CN109535164; (2019); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 63286-28-2, name is 2-Chloro-3-hydrazinylpyrazine, belongs to pyrazines compound, 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 63286-28-2, COA of Formula: C4H5ClN4

Step 2: 8-chloro-3-methyl-[l,2,4]triazolo[4,3-a]pyrazine [0197] To a stirred solution of 2-chloro-3-hydrazinylpyrazine (2.0 g, 14 mmol) in xylene (20 mL) was added triethyl orthoformate (5.8 mL, 32 mmol). The mixture was heated under reflux overnight and then cooled to room temperature. The resulting precipitate was collected by filtration to afford the title compound as a brown powder (2.0 g, 87%). MS (ESI) calcd forC6H5CIN4: 168.0 ; found: 169.2 [M+H]. *H NM (400 MHz, CDCI3) delta 7.80 (d, J = 4.8 Hz, 1H), 7.71 (d, J = 4.8 Hz, 1H), 2.83 (s, 3H).

If you are interested in these compounds, you can also browse my other articles.Thank you for taking the time to read this article. I hope you enjoyed it.

Reference:
Patent; RUGEN HOLDINGS (CAYMAN) LIMITED; SHAPIRO, Gideon; (239 pag.)WO2016/100349; (2016); A2;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 63744-29-6, A common heterocyclic compound, 63744-29-6, name is 5-Bromo-[1,2,4]triazolo[4,3-a]pyrazine, molecular formula is C5H3BrN4, 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 1.30. (3 ?,4S)-4-methylbenzyl 4-(([l,2,4]triazolo[4,3-a]pyrazin-5-ylamino)methyl)-3-fluoro- piperidine-l-carboxylate (E2-2.2). [0269] A mixture of 5-bromo-[l,2,4]triazolo[4,3-a]pyrazine (160 mg, 0.80 mmol), (3R,4S)-4- methylbenzyl 4-(aminomethyl)-3-fluoropiperidine-l-carboxylate hydrochloride (306 mg, 0.96 mmol), Brettphos precatalyst (20 mg), Brettphos (20 mg), and Cs2C03 (789 mg, 2.4 mmol) in t-BuOH (6 mL) was heated to 100C in the sealed tube under N2 atmosphere. After stirring overnight at 100C, the mixture was cooled down to room temperature and concentrated under vacuum. The concentrate was partitioned into DCM and water. The aqueous phase was extracted with DCM. The combined organic phases were washed with water, brine, dried over Na2S04 and concentrated. The concentrate was purified by column chromatography over silica gel (eluent: 100% ethyl acetate) to afford the title compound as a brown powder (92 mg, 28%). MS (ESI) calcd for C2oH23FN602: 398.2; found: 399.3[M+H]. *H NMR (400 MHz, CDCI3) delta 8.72 (s, 1H), 7.41 (d, J = 4.4 Hz, 1H), 7.34 (d, J = 4.4 Hz, 1H), 7.25 (d, J = 7.2 Hz, 2H), 7.17 (d, J = 7.2 Hz, 2H), 6.58 (br s, 1H), 5.09 (br s, 2H), 4.90-4.69 (m, 1H), 4.65-4.15 (m, 2H), 3.75-3.60 (m, 2H), 3.02-2.70 (m, 2H), 2.35 (s, 3H), 2.24-2.08 (m, 1H), 1.75- 1.65 (m, 2H).

The synthetic route of 63744-29-6 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; RUGEN HOLDINGS (CAYMAN) LIMITED; SHAPIRO, Gideon; (239 pag.)WO2016/100349; (2016); A2;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 1458-01-1,Some common heterocyclic compound, 1458-01-1, name is Methyl 3,5-diamino-6-chloropyrazine-2-carboxylate, molecular formula is C6H7ClN4O2, 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.

(1) A mixture of 20 g (99.0 mmol) of methyl 3,5-diamino-6-chloropyrazine-2-carboxylate (see U.S. Pat. No. 4,029,816 for an example of how to obtain this material) and 17 g (230.0 mmol) of N-methylethylenediamine was heated at reflux under an inert atmosphere for 30 hours. The rection mixture was cooled to ambient temperature and the solid was dissolved in 100 ml of tetrahydrofuran. The solution was filtered and evaporated. The residue was crystallized from 2-propanol. There was obtained 15.0 g (61.2 mmol, 61percent) of 3,5-diamino-6-chloro-N-(2-methylaminoethyl)pyrazine-2-carboxamide; mp 142.5°-143° C. Analysis calculated for; C8 H13 ClN6 O: C, 39.27; H, 5.35; N, 34.35; Found: C, 39.28; H, 5.26; N, 34.55.

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route Methyl 3,5-diamino-6-chloropyrazine-2-carboxylate, its application will become more common.

Reference:
Patent; ICI Americas Inc.; US4910202; (1990); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 5049-61-6,Some common heterocyclic compound, 5049-61-6, name is Pyrazin-2-amine, molecular formula is C4H5N3, 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.

2-Aminopyrazine (4 g, 42 mmol) was dissolved in water (2 mL) and DMSO (70 mL), and BS (7.5 g, 42 mmol) was added over 1 hour at 0C. The reaction was warmed to room temperature and stirred overnight. The mixture was poured onto ice and extracted 4 times with EtOAc. The combined organic layers were washed with 5% Na2C03, water, and brine, dried over MgS04, filtered, and concentrated. The residue was purified on silica gel to give the desired product.

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

Reference:
Patent; AUTOIMMUNE PHARMA LLC; BENISON, Jeffrey; (157 pag.)WO2018/152405; (2018); 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. 6905-47-1, name is 2-Amino-6-methoxypyrazine, A new synthetic method of this compound is introduced below., category: Pyrazines

-N-Chlorosuccinimide (1.7 g) was added portionwise to a solution of 2-amino-6-methoxypyrazine (S K Vohra et al, J. Org. Chem., 1979,44,1128; 1.6 g) in chloroform(26 ml) and the resultant mixture was stirred at ambient temperature for 3 hours. Silica gel (10g) was added and the solvents were evaporated. The residue was purified by columnchromatography on silica gel using methylene chloride as eluent. There were thus obtained inturn :- 2-amino-3,5-dichloro-6-methoxypyrazine (0.253 g); NMR Spectrum: (CDC13) 3.95 (s,3H), 4.83 (m, 2H); Mass Spectrum: M+H* 194; a sample of 3-amino-2-chloro-5-methoxypyrazine that was contaminated with succinimide and 5-amino-2-chloro-3-methoxypyrazine (0.339 g); NMR Spectrum: (CDC13) 3.95 (s, 3H), 4.27 (m, 2H), 7.32 (s,1H); Mass Spectrum: M+BT1″ 160. The fraction containing 3-amino-2-chloro-5-methoxypyrazine was purified further by column chromatography on silica gel eluting with a10:1 mixture of petroleum ether (b.p. 40-60C) and ethyl acetate. There was thus obtainedpurified material (0.94 g); NMR Spectrum: (CDC13) 3.87 (s, 3H), 4.82 (m, 2H), 7.36 (s, 1H);Mass Spectrum: M+H4″ 160.

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; WO2004/108703; (2004); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem