Month: April 2021

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. 768-05-8, name is Pyrazinoic acid hydrazide, A new synthetic method of this compound is introduced below., Application In Synthesis of Pyrazinoic acid hydrazide

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.

The synthetic route of 768-05-8 has been constantly updated, and we look forward to future research findings.

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

Adding a certain compound to certain chemical reactions, such as: 4745-93-1, name is 5H-Pyrrolo[2,3-b]pyrazine, 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 4745-93-1, Formula: C6H5N3

Example 3; Synthesis of (6-methoxy-pyridin-3-ylmethyl)-[5-(5H-pyrrolo[2,3-b]pyrazin-7-ylmethyl)-pyridin-2-yl]-amine P-0001; (6-Methoxy-pyridin-3-ylmethyl)-[5-(5H-pyrrolo[2,3-b]pyrazin-7-ylmethyl)-pyridin-2-yl]-amine P-0001 was prepared in two steps from 5H-pyrrolo[2,3-b]pyrazine 3 as shown in Scheme 1. Step 1-Synthesis of {5-[hydroxy-(5H-pyrrolo[2,3-b]pyrazin-7-yl)-methyl]-pyridin-2-yl}-(6-methoxy-pyridin-3-ylmethyl)-carbamic acid tert-butyl ester (7); To 5H-Pyrrolo[2,3-b]pyrazine (3, 0.150 g, 1.26 mmol) in 2.2 mL of methanol, (5-formyl-pyridin-2-yl)-(6-methoxy-pyridin-3-ylmethyl)-carbamic acid tert-butyl ester (6, 0.52 g, 1.5 mmol) and potassium hydroxide (0.230 g, 4.10 mmol) were added. The reaction was allowed to stir at room temperature overnight, then concentrated and poured into saturated sodium bicarbonate, and extracted with ethyl acetate. The organic portion was washed with brine, dried over anhydrous sodium sulfate, and filtered. The filtrate was concentrated under vacuum and purified by silica gel chromatography to provide the desired compound (7, 0.22 g, 38%).

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; Ibrahim, Prabha N.; Bremer, Ryan; US2009/306086; (2009); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 762240-92-6, 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. 762240-92-6 name is 3-(Trifluoromethyl)-5,6,7,8-tetrahydro-[1,2,4]triazolo[4,3-a]pyrazine hydrochloride, 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-17:Preparation of (R)-3-azido-l-(3-(trifluoromethyl)-5,6-dihydro-[l,2,4] triazolo[43-a]pyrazin-7(8H)-yl)-4-(2,4,5-trifluorophenyl)butan-l-one.;To 6 gms of (R)-methyl 3-azido-4-(2,4,5-trifluorophenyl)butanoate, added 30 ml of water and 30 ml of tetrahydrofuran. Added 2.0 gms of lithium hydroxide and stirred the reaction mixture for 4 hrs at 25-300C temperature. Acidify the reaction mixture using cone, hydrochloric acid and extracted the compound using ethyl acetate. Distilled off the solvent completely under reduced pressure. To the obtained residue added 24 ml of dimethylformamide and cooled the reaction mixture to 0-50C. 3.5 gms of N,N’- dicyclohexylcarbodiimide (DCC) was dissolved in 10 ml of dimethylformamide and make upto 20 ml. Added 7 ml of above prepared NjN’-dicyclohexylcarbodiimide (DCC) solution to the above 0-50C cooled reaction mixture. Added 3.5 gms of 3- (trifluoromethyl)-5,6,7,8-tetra hydro-[l,2,4]triazolo[4,3-a]pyrazine hydrochloride and 3.3 ml of triethylamine to the reaction mixture and stirred for 15 minutes. Added 0.75 gms of dimethylaminopyridine (DMAP) and stirred the reaction mixture for 3 hrs at 0-50C. Added 6.5 ml of N,N’-dicyclohexylcarbodiimide solution and stirred for 3 hrs. Again added 6.5 ml of N,N’-dicyclohexylcarbodiimide solution and stirred for 3 hrs at 0-50C. Raised the temperature to 25C and stirred the reaction mixture for 12 hrs at same temperature. The unwanted precipitated solids were separated by filtration and to the filtrate added water and ethyl acetate. Separated the both aqueous and organic layers. Washed the organic layer with 5% hydrochloric acid solution followed by washed with 5% sodium bicarbonate solution. Distilled off the solvent completely under reduced pressure. Added 30 ml of isopropyl alcohol to the obtained compound and stirred for 45 minutes at 25-300C temperature. Filtered the precipitated solid and dried the material. To the obtained compound added 10 ml of isopropyl alcohol and 3.8 ml of cone, hydrochloric acid. Stirred the reaction mixture for 3 hrs at 500C. Cooled the reaction mixture to 25C and added water. Extracted the compound from reaction mixture with methylene chloride. Distilled off the solvent completely to get the title compound. Yield: 4.5 gms.

At the same time, in my other blogs, there are other synthetic methods of this type of compound, 3-(Trifluoromethyl)-5,6,7,8-tetrahydro-[1,2,4]triazolo[4,3-a]pyrazine hydrochloride, and friends who are interested can also refer to it.

Reference:
Patent; MSN LABORATORIES LIMITED; SATYANARAYANA REDDY, Manne; ESWARAIAH, Sajja; SATYANARAYANA, Revu; KONDAL REDDY, Bairy; SRINIVAS, Aluru; WO2010/122578; (2010); A2;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 22047-25-2, 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. 22047-25-2, name is Acetylpyrazine, This compound has unique chemical properties. The synthetic route is as follows.

Step 1: Preparation of 4,4-difluoro-1-(2-pyrazinyl)-butane-1,3-dione Ethyl difluoroacetate (2.23 g, 18 mmol) was placed in a 100 mL round bottom flask and dissolved in ether (10 mL). To the stirred solution was added 25% sodium methoxide (4.68 g, 22 mmol) followed by acetylpyrazine (2.00 g, 16 mmol). After two hours stirring at room temperature, a precipitate formed and THF (10 mL) was added to the reaction. The reaction was stirred an additional 25.9 hours, then treated with 3N HCl (10 mL). The organic layer was collected, washed with brine (20 mL), dried over MgSO4, and concentrated in vacuo and recrystallized from methylene chloride/iso-octane to give the diketone as a brown solid (2.23 g, 68%); mp 103-110 C.; 1 H NMR (CDCl3) 300 MHz 14.00 (br s, 1H), 9.31 (d, J=1.4 Hz, 1H), 8.76 (d, J=2.4 Hz, 1H), 8.68 (dd, J=1.4 Hz 2.4 Hz, 1H), 7.20 (s, 1H), 6.03 (t, J=54.0 Hz, 1H); 19 F NMR (CDCl3) 300 MHz: -127.16 (d); M+ 200.

The chemical industry reduces the impact on the environment during synthesis Acetylpyrazine. I believe this compound will play a more active role in future production and life.

Reference:
Patent; G.D. Searle & Co.; US5760068; (1998); A;,
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. 19847-12-2, name is Pyrazinecarbonitrile, This compound has unique chemical properties. The synthetic route is as follows., category: Pyrazines

Pyrazine-2-carbonitrile 1g (10.5 g, 100 mmol) was dissolved in 150 mL of 1,4-dioxane, then Raney nickel (1.0 g) was added into a 250 mL autoclave. The reaction mixture was reacted in hydrogen atmosphere for 8 hours under 40 atmosphere at 60 C. and filtered and concentrated under reduced pressure to obtain the title compound C-pyrazin-2-yl-methyl amine 1h (10.7 g, yield 98%) as a brown oil. MS m/z (ESI): 110 [M+1].

According to the analysis of related databases, 19847-12-2, the application of this compound in the production field has become more and more popular.

Reference:
Patent; SHANGHAI HENGRUI PHARMACEUTICAL CO., LTD.; JIANGSU HENGRUI MEDICINE CO., LTD.; US2012/65209; (2012); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 19847-12-2, In the chemical reaction process, reaction time, type of solvent, can easily affect the result of the reaction, thereby determining the yield and properties of the reaction product. An updated downstream synthesis route of 19847-12-2 as follows.

Example 8. Synthesis of the primary amine, pyrazin-2-ylmethanaminechromatography 17 3. TFA / CH2CI2 18[0096] Raney nickel catalyst was carefully washed with THF and methanol making sure that the catalyst remained moist. The weight of the moist catalyst was 2.5 g after washing. This material was added to a solution of pyrazinecarbonitrile (17) (3.0 g) in 7N methanolic ammonia (120 mL). The mixture was shaken under a 50 p.s.i. atmosphere of hydrogen for 1.5 hours. The mixture was filtered and the filtrate was concentrated in vacuo to provide the crude title compound. Purification was accomplished by conversion of the crude amine to the tert-butyl carbamate with excess di-fert-butyl dicarbonate in methylene chloride. Column chromatography (70:27:3 hexanes:ethyl acetate:methanol) provided 0.5O g of pure tert-butyl pyrazin-2-ylmethylcarbamate. Pure pyrazin-2- ylmethanamine (18) was obtained as the TFA salt from deprotection of the carbamate with 1:1 TFA / CH2Cl2. EPO [0097]

According to the analysis of related databases, 19847-12-2, the application of this compound in the production field has become more and more popular.

Reference:
Patent; PHARMACOPEIA DRUG DISCOVERY, INC.; WO2006/108103; (2006); 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. 4774-14-5, name is 2,6-Dichloropyrazine, A new synthetic method of this compound is introduced below., Formula: C4H2Cl2N2

3. 2-Chloro-6-amino-pyrazine A suspension of 2,6-dichloropyrazine (100 g, 0.67 mole, Lancaster) in 0.880 ammonia (500 ml) was stirred and heated at 150 C. in a glass lined autoclave at 20 atm for 16 hrs. The cooled mixture was filtered, washed well with water (200 ml) and dried. The product was recrystallized from chloroform. Yield 41.98 g (48%), M.p. 150-152 C.

The synthetic route of 4774-14-5 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Glaxo Wellcome, Inc.; US6255307; (2001); B1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 4430-75-5, The chemical industry reduces the impact on the environment during synthesis 4430-75-5, name is Octahydro-2H-pyrido[1,2-a]pyrazine, I believe this compound will play a more active role in future production and life.

2,3,4,6,7,8,9,9a-Octahydro-1H-pyrido[1,2-a]pyrazine (477 mg, 3.40 mmol) was added in one portion to 5-chloro-N-[5-[2-(3,5-dimethoxyphenyl)ethyl]-2H-pyrazol-3-yl]pyrazine-2-carboxamide (659 mg, 1.70 mmol) in anhydrous dimethylsulfoxide (1.70 ml) at 25 C. The resulting solution was stirred at 100 C. for 18 h. The crude product was purified by ion exchange chromatography, using an SCX column. The desired product was eluted from the column using 7M NH3/MeOH to afford impure material. The concentrated eluant was purified by preparative HPLC, using decreasingly polar mixtures of water (containing 1% formic acid) and MeCN as eluents. The sample was then put through a basic HPLC system to obtain the free base. Fractions containing the desired compound were evaporated to dryness to afford the title compound (395 mg, 47%) as a cream solid. 1H NMR (500.133 MHz, DMSO) delta 1.19-1.35 (3H, m), 1.51-1.60 (1H, m), 1.64 (1H, t), 1.73-1.79 (1H, m), 1.93-2.08 (2H, m), 2.17-2.25 (1H, m), 2.73 (1H, dd), 2.81-2.93 (6H, m), 3.13 (1H, td), 3.73 (6H, s), 4.28-4.33 (1H, m), 4.37-4.42 (1H, m), 6.32 (1H, t), 6.38-6.41 (3H, m), 8.26 (1H, d), 8.70 (1H, d), 9.59 (1H, br s), 11.82 (1H, br s). MS: m/z 492 (MH+). Mean of n=1, FGFR Kinase assay-Caliper Echo Dosing, IC50 0.13 muM.

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, Octahydro-2H-pyrido[1,2-a]pyrazine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; ASTRAZENECA AB; US2008/153812; (2008); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 6966-01-4,Some common heterocyclic compound, 6966-01-4, name is Methyl 3-amino-6-bromopyrazine-2-carboxylate, molecular formula is C6H6BrN3O2, 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.

Pd(dppf)CI2 (158 mg, 0.215 mmol) was added to a suspension of methyl 3-amino-6- bromopyrazine-2-carboxylate (1.00 g, 4.31 mmol), ethylboronic acid (0.637 g, 8.62 mmol) and K2CO3 (1.79 g, 12.9 mmol) in DME (20 ml). The resultant suspension was de-gassed by bubbling a stream of nitrogen through the reaction mixture for 1 min. The reaction mixture was heated at 90 C for 17 h then allowed to cool to RT. The reaction was recharged with ethylboronic acid (318 mg, 4.31 mmol) and Pd(dppf)Cl2 (79 mg, 0.11 mmol) then heated at 90 C for 2 h. The reaction mixture was allowed to cool to RT then added to saturated aq. NaHC03 solution (40 ml). The resultant mixture was extracted with EtOAc (2×40 ml) then the combined organic extracts were washed with brine (40 ml), dried over MgS0 , filtered and concentrated in vacuo. The crude material was purified by flash column chromatography on a silica column (50 g). The column was eluted with EtOAc: heptane, increasing the gradient linearly from 6:94 to 50:50 over 10 column volumes. The desired fractions were combined and evaporated to yield the product as a yellow solid (322 mg, 41 %).1H NMR (250 MHz, CDCl3 ) delta 8.14 (s, 1 H), 6.27 (s, 2H), 3.98 (s, 3H), 2.79 (q, J = 7.6 Hz, 2H), 1.29 (t, J = 7.6 Hz, 3H).LC/MS (System A): m/z (ESI+) = 182 [MH+], Rt = 0.81 min, UV purity = 100%.

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-amino-6-bromopyrazine-2-carboxylate, its application will become more common.

Reference:
Patent; ENTERPRISE THERAPEUTICS LIMITED; MCCARTHY, Clive; HARGRAVE, Jonathan David; HAY, Duncan Alexander; SCHOFIELD, Thomas Beauregard; WENT, Naomi; (111 pag.)WO2017/221008; (2017); 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. 41270-62-6, name is 2-Chloro-6-phenylpyrazine, A new synthetic method of this compound is introduced below., name: 2-Chloro-6-phenylpyrazine

To a mixture of tert-butyl (S)-2-amino-4-(((R)-2-methoxypropyl) (4-(5,6,7,8-tetrahydro-1,8-naphthyridin-2-yl) butyl)amino) butanoate (200 mg, 460 mumol) and 2-chloro-6-phenyl-pyrazine (73 mg, 383 mumol) in t-AmOH (3 mL) was added 2.0M NaO-tBu (382 muL, 764 mol) then tBuXPhos-Pd-G3 (30 mg, 38 mumol) and the resulting mixture was heated to 100 C. for 15 h and then cooled to rt and then concentrated in vacuo to give a (S)-tert-butyl 4-(((R)-2-methoxypropyl) (4-(5,6,7,8-tetrahydro-1,8-naphthyridin-2-yl) butyl)amino)-2-((6-phenylpyrazin-2-yl) amino) butanoate intermediate, LCMS (ESI+): m/z=589.5 (M+H), which was used without further purification. Of the butanoate intermediate, 280 mg, 476 mumol was taken up into DCM (2 mL), and TFA (1.1 mL) and the resulting mixture was stirred at rt for 6 h and concentrated in vacuo. The crude residue was purified by prep-HPLC to give the title compound. LCMS (ESI+): m/z=533.3 (M+H). H NMR (400 MHz, Methanol-d4) delta ppm 8.21 (s, 1H) 7.97-8.04 (m, 2H) 7.90 (s, 1H) 7.38-7.47 (m, 3H) 7.23 (d, J=7.28 Hz, 1H) 6.43 (d, J=7.28 Hz, 1H) 4.54 (dd, J=7.17, 4.74 Hz, 1H) 3.69-3.79 (m, 1H) 3.32-3.48 (m, 2H) 3.30 (s, 3H) 3.23-3.29 (m, 2H) 2.98-3.15 (m, 4H) 2.56-2.70 (m, 4H) 2.30-2.42 (m, 1H) 2.13-2.25 (m, 1H) 1.70-1.86 (m, 6H) 1.13 (d, J=6.17 Hz, 3H).

The synthetic route of 41270-62-6 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Pliant Therapeutics, Inc.; CHA, Jacob; DONG, Chengguo; HOM, Timothy; JIANG, Lan; LEFTHERIS, Katerina; LI, Hui; MORGANS, JR., David J.; MUNOZ, Manuel; REILLY, Maureen; ZHENG, Yajun; (232 pag.)US2019/276449; (2019); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem