Tag: M.W=100-200

Electric Literature of 54608-52-5,Some common heterocyclic compound, 54608-52-5, name is 2-Hydrazinopyrazine, molecular formula is C4H6N4, 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 15.0 g (136 mmol) of 2-hydrazinopyrazine in 100 ML of trimethyl orthoformate was heated to reflux at 100 C for 1.5 h. The solvent was removed in vacuo and the crude product was applied to a pad of silica gel and eluted with 15: 85 methanol : ethyl acetate. The resulting solution was concentrated in vacuo to yield the title compound. LC/MS 121.0 (M+1).

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

Reference:
Patent; MERCK & CO., INC.; WO2004/58266; (2004); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 54608-52-5, 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 54608-52-5 as follows.

General procedure: To a well-stirred solution of I 2 (0.2 mmol)TBHP (2 mmol,70% in water) K2CO3 (1 mmol) in 1,4-dioxane (10 mL) were added benzaldehyde 1a (1 mmol) and 2-hydrazinopyridine 2a (1 mmol), and then the reaction mixture was stirred at 60 C. After completion of the raction as indicated by TLC (1 h), the reaction mixture was cooled to room temperature. Then the reaction mixture was treated with 10 % Na2S2O3 (20 mL) and extracted with ethyl acetate (10 mL×3). The combined organic layer was dried over anhydrous Na2SO4 and concentrated under reduced pressure. The crude product was purified through silica gel column chromatography using a mixture of EtOAc and petroleum ether as eluent to afford the targeted product in 72-97 % yield.

According to the analysis of related databases, 54608-52-5, the application of this compound in the production field has become more and more popular.

Reference:
Article; Wu, Yachuang; Yang, Yifeng; Qi, Yinliang; Du, Shimei; Zhang, Yongsheng; Ding, Liang; Zhao, Yanfang; Tetrahedron Letters; vol. 59; 48; (2018); p. 4216 – 4220;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

These common heterocyclic compound, 63286-28-2, name is 2-Chloro-3-hydrazinylpyrazine, 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: 2-Chloro-3-hydrazinylpyrazine

A mixture of l-(3-chloropyrazin-2-yl)hydrazine (0.90 g, 62 mmol), triethyl orthoformate (2.3 mL), 14 mmol), and dry xylene (15 mL) was refluxed with stirring for 2 h. The mixture was brought to RT, diethyl ether was added and the suspension was filtered. The solid collected was washed with diethyl ether to afford 8-chloro-[l,2,4]triazolo[4,3- ajpyrazine (0.60 g, 62% yield). MS m/z: 155.0 (M+l).

The synthetic route of 2-Chloro-3-hydrazinylpyrazine has been constantly updated, and we look forward to future research findings.

Reference:
Patent; AMGEN INC.; WO2009/64418; (2009); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 74290-67-8, 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. 74290-67-8 name is 2-Amino-5-bromo-3-methylpyrazine, 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.

a) 3-(N-(3-((5-amino-6-methylpyrazin-2-yl)ethynyl)-2,4-difluorophenyl)sulfamoyl)-5-chloro-2-methoxybenzyl Acetate A mixture of 5-chloro-3-(N-(3-ethynyl-2,4-difluorophenyl)sulfamoyl)-2-methoxybenzyl acetate (200 mg), dichlorobis(tricyclohexylphosphine)palladium(II) (34.3 mg), DIPEA (2 mL), copper(I) iodide (17.7 mg), 5-bromo-3-methylpyrazin-2-amine (114 mg) and DMSO (2 mL) was stirred under microwave irradiation at 100 C. for 1 hr. After cooling to room temperature, the reaction mixture was diluted with water and extracted with ethyl acetate. The obtained organic layer was washed with saturated brine, dried over magnesium sulfate and concentrated to give a residue. The residue was purified by silica gel column chromatography (ethyl acetate/hexane) to give the title compound (216 mg). MS: [M+H]+ 537.0.

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

Reference:
Patent; Takeda Pharmaceutical Company Limited; FUJIMOTO, Jun; LIU, Xin; KURASAWA, Osamu; TAKAGI, Terufumi; CARY, Douglas Robert; BANNO, Hiroshi; ASANO, Yasutomi; KOJIMA, Takuto; (159 pag.)US2019/169166; (2019); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 4858-85-9, name is 2,3-Dichloropyrazine, 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 4858-85-9, Recommanded Product: 4858-85-9

A mixture 2,3-dichloro-pyrazine (5.0 g, 34 mmol), 1-isopropylpiperazine (6.5 g, 51 mmol) and potassium carbonate (7.0 g, 51 mmol) in acetonitrile (100 mL) was stirred at ambient temperature for 2 h. Addition of hexane, followed by filtration and concentration of the filtrate gave 9.5 g of crude material as an orange liquid. Purification by filtration through silica using heptane/EtOAc (3: 1), followed by EtOAc/acetone (1: 1), provided 6.5 g (79%) of the title compound as a yellow oil which solidified upon cooling. HPLC purity: 98%. MS m/z 241 (M+H) +. HRMS m/z calcd for C11H17ClN4 (M) + 240.1142, found 240.1138.

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

Reference:
Patent; BIOVITRUM AB; WO2004/9586; (2004); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 109838-85-9, 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. 109838-85-9 name is (R)-2-Isopropyl-3,6-dimethoxy-2,5-dihydropyrazine, 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.

[0562] A solution of compound 4-01-5 (8.9 g, 48 mmol) in tetrahydrofuran (100 mL) was cooled to -70C and n-butyl lithium (2.5 M, 19.5 mL, 49 mmol) was added under nitrogen while the temperature was kept below -70C. A solution of compound 7- bromohept-l-ene (8.0 g, 45 mmol) in tetrahydrofuran (15 mL) was added at -70C. The reaction mixture was stirred at -70C for 2 hours, then slowly heated to 20C and stirred for 1 hour. The reaction mixture was poured into saturated ammonium chloride solution (50 mL) and extracted with ethyl acetate (200 mL *2). The combined organic phase was washed with brine (100 mL*2), dried over anhydrous sodium sulfate, and concentrated in reduced pressure. The residue was purified by column chromatography (petroleum ether to petroleum ether: ethyl acetate = 50: 1) to afford compound 4-01-6 (7 g, 55% yield) as a colorless oil.

At the same time, in my other blogs, there are other synthetic methods of this type of compound, (R)-2-Isopropyl-3,6-dimethoxy-2,5-dihydropyrazine, and friends who are interested can also refer to it.

Reference:
Patent; CORNELL UNIVERSITY; TRI-INSTITUTIONAL THERAPEUTICS DISCOVERY INSTITUTE; LIN, Gang; NATHAN, Carl; KIRKMAN, Laura; ZHAN, Wenhu; MORGAN, Trevor; SATO, Kenjiro; HARA, Ryoma; KAWASAKI, Masanori; IMAEDA, Toshihiro; TOITA, Akinori; OKAMOTO, Rei; YUKAWA, Takafumi; ASO, Kazuyoshi; WONG, Tzu-Tshin; GINN, John, D.; FOLEY, Michael, A.; (296 pag.)WO2019/75259; (2019); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

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 113305-94-5 as follows. Quality Control of 5-Aminopyrazine-2-carbonitrile

The 5-aminopyrazine-2-carbonitrile (commercially available, 1.0 g, 8.32 mmol) was dissolved in tetrahydrofuran then succinic anhydride (1.04 g, 10.4 mmol) was added, the mixture was stirred at room temperature for 2 h and at reflux overnight.. Then 1.0 equivalent of succinic anhydride was added and the solution was re fluxed for 4 days. The reaction was stopped and the solution was partitioned between ethyl acetate and water. The aqueous layer was separated, acidified and extracted with ethyl acetate (3x). The combined organic layer was dried on magnesium sulfate and concentrated under vaccum. The residue was purified by flash chromatography eluting with cyclohexane-ethyl acetate (1/3) with acid acetic (1%) to give 4-[(5-cyanopyrazin-2-yl)amino]-4-oxo-butanoic acid Al (1.30 g, 71%). M.p.= 201-202 C, 1H NMR (400 MHz, DMSO-d6) ? 12.09 (bs, 1H), 11.40 (s, 1H), 9.41(s, 1H), 8.96 (s, 1H), 2.73 (t, 2H), 2.55 (t, 2H) ppm. LC-MS (Method B): RT 0.96, 219 (M-H+)

According to the analysis of related databases, 113305-94-5, the application of this compound in the production field has become more and more popular.

Reference:
Patent; SYNGENTA PARTICIPATIONS AG; JUNG, Pierre Joseph Marcel; LEIPNER, Joerg; LACHIA, Mathilde Denise; DE MESMAEKER, Alain; WO2013/37753; (2013); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 4744-50-7, 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. 4744-50-7, name is 2,3-Pyrazinecarboxylic anhydride belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below.

General procedure: Pyrazine-2,3-dicarboxylic anhydride (1.0 g, 6.7 mmol) was dissolved in tetrahydrofuran (40 mL)in an Erlenmeyer flask and the corresponding substituted aniline (6.7 mmol, 1 equiv.) was added in one dose. The reaction mixture was stirred for 1 hour at laboratory temperature. Water (30 mL) was added into the mixture followed by the saturated aqueous solution of NaHCO3 until pH 6 to form thecorresponding 3-(phenylcarbamoyl)pyrazine-2-carboxylic acid 1-18. Obtained crystals were filtered off and washed with water. The progress of the procedure was monitored by TLC eluted with thesystem water/butanol/acetic acid 5:4:1.

The synthetic route of 2,3-Pyrazinecarboxylic anhydride has been constantly updated, and we look forward to future research findings.

Reference:
Article; Semelkova, Lucia; Jano?cova, Petra; Fernandes, Carlos; Bouz, Ghada; Jand?Ourek, Ond?ej; Kone?na, Klara; Paterova, Pavla; Navratilova, Lucie; Kune?, Ji?i; Dole?al, Martin; Zitko, Jan; Molecules; vol. 22; 9; (2017);,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 22047-25-2, 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. 22047-25-2, name is Acetylpyrazine belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below.

[Reference Example 6] 1-(6-Methoxy-3-pyridyl)-5-(2-pyrazinyl)-1H-pyrazole-3-carboxylic acid [Show Image] [Show Image] Lithium bis(trimethylsilyl)amide (a 1.0 M solution in tetrahydrofuran, 11.0 mL) was added to a solution of 1-(2-pyrazinyl)-1-ethanone (1.22 g) in tetrahydrofuran (10 mL) under cooling to -78C, and the resultant mixture was stirred for 55 minutes. Diethyl oxalate (2.05 mL) was added thereto, and the mixture was slowly returned to room temperature, and stirred for 6.5 hours. An aqueous 1 N hydrochloric acid solution (11 mL), water and diethyl ether were added to the reaction solution, and the mixture was partitioned. Then, sodium chloride was added to the aqueous layer to be saturated, and then ethyl acetate was added for extraction. The organic layers were combined, and the solvent was evaporated under reduced pressure, to obtain a crude product of 4-(2-pyrazinyl)-2, 4-dioxobutanoic acid ethyl ester (1.83 g, 82%) as a solid. To a suspension of this crude product (1.58 g) in ethanol (20 mL), a solution formed from a suspension of 5-hydrazino-2-methoxypyridine hydrochloride (1.50 g) of Reference Example 1 in ethanol (80 mL) conditioned with triethylamine (1.9 mL), was added, and the mixture was heated to reflux for 19 hours. Acetic acid (5 mL) was further added to the reaction solution, and the mixture was heated to reflux for 1.5 days. After air cooling, ethyl acetate and a saturated aqueous solution of sodium hydrogen carbonate were added to the reaction solution, and the mixture was partitioned. The organic layer was dried over anhydrous sodium sulfate. After separation by filtration, a residue obtained by evaporating the solvent under reduced pressure was purified by silica gel column chromatography (ethyl acetate-hexane), to obtain 1-(6-methoxy-3-pyridyl)-5-(2-pyrazinyl)-1H-pyrazole-3-carboxylic acid ethyl ester (1.05 g, 45%) as a solid. To a solution of this obtained 1H-pyrazole-3-carboxylic acid ethyl ester product (1.05 g) in ethanol (30 mL), an aqueous 1 N sodium hydroxide solution (10.0 mL) was added, and the mixture was stirred for 16 hours at room temperature. An aqueous 1 N hydrochloric acid solution (15 mL), water and ethyl acetate were added to the reaction solution, and the mixture was partitioned. The organic layer was dried over anhydrous magnesium sulfate. After separation by filtration, the solvent was evaporated under reduced pressure, to obtain a crude product of the title compound (0.883 g, 92%) as a solid. This product was supplied to the subsequent reaction without being purified.

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, Acetylpyrazine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; DAIICHI PHARMACEUTICAL CO., LTD.; EP1785418; (2007); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 4744-50-7, A common heterocyclic compound, 4744-50-7, name is 2,3-Pyrazinecarboxylic anhydride, molecular formula is C6H2N2O3, 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: Pyrazine-2,3-dicarboxylic anhydride (1.0 g, 6.7 mmol) was dissolved in tetrahydrofuran (40 mL)in an Erlenmeyer flask and the corresponding substituted aniline (6.7 mmol, 1 equiv.) was added in one dose. The reaction mixture was stirred for 1 hour at laboratory temperature. Water (30 mL) was added into the mixture followed by the saturated aqueous solution of NaHCO3 until pH 6 to form thecorresponding 3-(phenylcarbamoyl)pyrazine-2-carboxylic acid 1-18. Obtained crystals were filtered off and washed with water. The progress of the procedure was monitored by TLC eluted with thesystem water/butanol/acetic acid 5:4:1.

The synthetic route of 4744-50-7 has been constantly updated, and we look forward to future research findings.

Reference:
Article; Semelkova, Lucia; Jano?cova, Petra; Fernandes, Carlos; Bouz, Ghada; Jand?Ourek, Ond?ej; Kone?na, Klara; Paterova, Pavla; Navratilova, Lucie; Kune?, Ji?i; Dole?al, Martin; Zitko, Jan; Molecules; vol. 22; 9; (2017);,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem