Month: July 2021

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. 63286-28-2, name is 2-Chloro-3-hydrazinylpyrazine belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below. COA of Formula: C4H5ClN4

2-Chloro-3-hydrazinylpyrazine C-l (15.6 g; 108 mmol) is slurried up in (300 ml) THF and cooled down in an ice bath to -5 C. Trifluoroacetic anhydride (17 ml; 118 mmol) is also dissolved in 300 ml THF and dropped slowly to the first solution. After 1 h most of the THF is evaporated, than a small amount of water is added and the mixture is extracted with DCM. The organic phase is dried over MgS04 and evaporated to dryness. Yield: 100 % HPLC-MS: (M+H)+ = 241/243; tRet = 1.31 min; method FSUN2

The synthetic route of 63286-28-2 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; BOEHRINGER INGELHEIM INTERNATIONAL GMBH; ENGELHARDT, Harald; WO2015/67770; (2015); 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. 221136-66-9, name is Ethyl 2-(3-bromo-6-methyl-2-oxopyrazin-1(2H)-yl)acetate, A new synthetic method of this compound is introduced below., Recommanded Product: 221136-66-9

Example 8 r3-(2,2-Difluoro-2-phenyl-ethylamino)-6-methyl-2-oxo-2H-pyrazin-1-vn- acetic acid ethyl ester(3-Bromo-6-methyl-2-oxo-2H-pyrazin-1 -yl)-acetic acid ethyl ester was reacted with 2,2-difluoro-2-phenyl-ethylamine in the presence of a base, at elevated temperature, to yield the title compound as shown in the Scheme above. Table 5 below lists the reagent amounts, base and temperature combinations applied to this reaction, as well as yield.

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; JANSSEN PHARMACEUTICA, N.V.; WO2007/146553; (2007); A2;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 4744-50-7,Some common heterocyclic compound, 4744-50-7, name is 2,3-Pyrazinecarboxylic anhydride, molecular formula is C6H2N2O3, 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: A mixture of an appropriate cyclic imides 1-14 (5.0 mmol), 4-(hydrazinecarbonyl)benzenesulfonamide (15) (1.08 g, 5.0 mmol), and anhydroussodium acetate (0.69 g, 5.0 mmol) in glacial acetic acid(20 mL) was heated under reflux for 12 h. After cooling the reactionmixture, the precipitate obtained was filtered, washed with water, driedand re-crystallised from acetic acid.

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 2,3-Pyrazinecarboxylic anhydride, its application will become more common.

Reference:
Article; Abdel-Aziz, Alaa A.-M.; El-Azab, Adel S.; Ghiaty, Adel H.; Gratteri, Paola; Supuran, Claudiu T.; Nocentini, Alessio; Bioorganic Chemistry; vol. 83; (2019); p. 198 – 204;,
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. 6966-01-4, name is Methyl 3-amino-6-bromopyrazine-2-carboxylate, A new synthetic method of this compound is introduced below., Quality Control of Methyl 3-amino-6-bromopyrazine-2-carboxylate

The 3-( lH-benzimidazol-2-yl)-5-(4-hydroxy-3-methoxyphenyl)pyrazin-2-amine used as a starting material was prepared as follows :- 2-Methoxy-4-(4,4,5,5-tetramethyl-l,3,2-dioxaborolan-2-yl)phenol (5.38 g) was added to a solution of methyl 3-amino-6-bromopyrazine-2-carboxylate (5.0 g) and potassium phosphate (16 g) in a 1:1:2 mixture of toluene: water:methanol (120 ml). Nitrogen was bubbled through the solution for 10 minutes before addition of bis(t-tert- butylphosphine)palladium (0.55 g). The mixture was heated to 600C for 1 hour. Ethyl acetate (120 ml) was added and the solution was extracted twice with IN aqueous sodium hydroxide (120 ml). The aqueous extracts were combined and acidified to peta 3 with hydrochloric acid. This solution was extracted with ethyl acetate (120 ml). The organic extract was dried over magnesiura sulphate and evaporated. The resultant residue was triturated under diethyl ether. The solid so obtained was filtered to give 3-amino-6-(4-hydroxy-3-methoxyrhohenyl)pyrazine- 2-carboxylic acid as a solid (4.65 g).

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; WO2009/7390; (2009); A2;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

51171-02-9, name is Methyl 3-Bromo-2-pyrazinecarboxylate, 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. Recommanded Product: Methyl 3-Bromo-2-pyrazinecarboxylate

(B) Methyl 2-phenylamino-3-pyrazine carboxylate A mixture of 9.5 g. of methyl 2-bromo-3-pyrazine carboxylate, 8.2 g. of aniline, 0.5 g. of p-toluene sulfonic acid and 100 ml. of water was stirred and refluxed for two hours. The reaction mixture was poured on ice, extracted with ethyl acetate, the organic extracts were dried and concentrated to yield an oil. The crude residue was eluted on a silica gel column with ethyl acetate-hexane (1:2) yielding the product of this example as a yellow solid, m.p. 72-75 C.

The synthetic route of 51171-02-9 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Schering Corporation; US4632923; (1986); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

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

To a solution of aminopyrazine (5 g, 53 mol, 1 eq.) in ethanol (212 ml) was added bromoacetaldehyde diethylacetal (12 ml, 80 mol, 1.5 eq.) and HBr (48%, 26.5 ml). The mixture was heated at 70-80 C. for 17 hours. The mixture was then cooled to rt (room temperature), then a mixture of 1N NaOH (200 ml) and 20% IPA/DCM (isopropyl alcohol/Dichloromethane) was added to the reaction mixture. The combined organic layer was dried over sodium sulfate and concentrated to afford 5.9 g of brown solid of imidazo[1,2-a]pyrazine (yield 94%). 1H-NMR (400 MHz, DMSO-d6) delta 9.05 (m, 1H), 8.60 (dd, 1H), 8.13 (d, 1H), 7.87 (d, 1H), 7.81 (d, 1H). MS m/z 120 [M++1].

The synthetic route of 5049-61-6 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Sugen, Inc.; US2004/220189; (2004); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 24241-18-7, 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.

To a solution of 3,5-dibromopyrazin-2-amine (10 g, 40 mmol), copper(I) iodide (0.91 g, 4.7 mmol), diisopropylethylamine (53 mL, 0.55 mol), and tetrakis(triphenylphosphine)-palladium(0) (2.3 g, 1.9 mmol) in DMF (120 mL) that was de-gassed with Ar was added trimethylsilylacetylene (6.7 mL, 48 mmol). The resulting mixture was stirred under an Ar atmosphere for 1 h at 1200C, after which it was evaporated to dryness in vacuo. The residue was subjected to silica gel chromatography eluting with 35% EtOAc in hexanes to give a brown oil that was triturated with hexanes to give the title compound (5.0 g, 47%). 1H NMR (CDCl3, 300 MHz): delta 8.04 (s, IH), 5.10 (s, 2 H), 0.28 (s, 9H). HPLC retention time: 2.75 minutes. MS ESI (m/z): 270.0, 272.0 (M+H) +, calc. 269.

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; UNIVERSITY OF ROCHESTER; GELBARD, Harris, A.; DEWHURST, Stephen; GOODFELLOW, Val, S.; WIEMANN, Torsten; WO2010/68483; (2010); A2;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 109838-85-9, A common heterocyclic compound, 109838-85-9, name is (R)-2-Isopropyl-3,6-dimethoxy-2,5-dihydropyrazine, molecular formula is C9H16N2O2, 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.

To a solution of (2R)-(-)-2,5-dihydro-3,6-dimethoxy-2-isopropylpyrazine(0.61 g, 4.36 mmol) in THF (8 mL) was added n-BuLi (2.5 M in hexane, 1.8 mL, 4.58 mmol) at -78 °C. After allowed to stir for 0.3 hours, Compound Int-15a (2.75 g, 6.98 mmol) in 2 mL of THF was added and the mixture was allowed to stir at the temperature for 4 hours. The reaction was quenched by saturated aqueous H4C1 solution and the organic layers were extracted with EtOAc. The combined organic solution was washed with brine solution, dried (Na2S04), and concentrated in vacuo. The residue obtained was purified using an ISCO 40 g column (gradient from 0percent to 2.5percent ether in hexane) to provide Compound Int-15b, 783 mg (44percent). 1H MR (CDC13) delta 4.05 (m, 1H), 3.96 (t, J= 3.4 Hz, 1H), 3.72 (s, 3H), 3.71 (s, 3H), 3.49 (dd, J= 2,8, 0.4 Hz, 1H), 3.26 (dd, J= 6, 9.4 Hz, 1H), 2.30 (m, 1H), 1.96 (m, 1H), 1.60 (m, 2H), 1.37-1.17 (m, 3H), 1.08 (d, J= 6.9 Hz, 3H), 0.99-0.86 (m, 2H), 0.72 (d, J= 6.6 Hz, 3H), 0.49 (dd, J= 11.0, 14.4 Hz, 1H), 0.35 (dd, J= 11.0, 14.2 Hz, 1H), 0.16 (s, 6H)

The synthetic route of 109838-85-9 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; MERCK SHARP & DOHME CORP.; KOZLOWSKI, Joseph, A; ROSENBLUM, Stuart, B; COBURN, Craig, A; SHANKAR, Bandarpalle, B; ANILKUMAR, G, Nair; CHEN, Lei; DWYER, Michael, P; JIANG, Yueheng; KEERTIKAR, Kartik, M; LAVEY, Brian, J; SELYUTIN, Oleg, B; TONG, Ling; WONG, Michael; YANG, De-Yi; YU, Wensheng; ZHOU, Guowei; WU, Hao; HU, Bin; ZHONG, Bin; SUN, Fei; JI, Tao; SHEN, Changmao; WO2012/40923; (2012); A1;; ; Patent; SCHERING CORPORATION; COBURN, Craig, A.; LAVEY, Brian, J.; DWYER, Michael, P.; KOZLOWSKI, Joseph, A.; ROSENBLUM, Stuart, B.; WO2012/50848; (2012); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

138588-41-7, name is Pyrazine-2-carboximidamide hydrochloride, 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. Safety of Pyrazine-2-carboximidamide hydrochloride

A stirred mixture of 5-(bromo-p-fluorophenyl-acetyl)-1-isopropyl-3-methyl-1, 3- dihydro-benzoimidozol-2-one (8) (0.5 g, 1.23 mmol), pyrazine-2-carboxamidine hydrochloride (0.395 g, 2,49 mmol), cesium carbonate (1.22 g, 3.74 mmol) and DMF (4.0 mL) was heated to 60 C. After 1 hour, the reaction was determined to be complete by LCMS. The reaction was cooled to room temperature and diluted with water (40 mL). After stirring for 1 hour, the crude suspension was filtered and the solids were purified by flash chromatography (diethyl ether, followed by ethyl acetate to afford 40 mg of the title compound (MAPKi No.2) as a light tan solid.

The synthetic route of 138588-41-7 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; PFIZER PRODUCTS INC.?; WO2005/60967; (2005); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 6966-01-4, 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. 6966-01-4, name is Methyl 3-amino-6-bromopyrazine-2-carboxylate belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below.

Step 1. Synthesis of methyl 3-amino-6-(4,4,5,5-tetramethyl-l,3,2-dioxaborolan-2- razine-2-carboxylate A mixture of methyl 3-amino-6-bromopyrazine-2-carboxylate (8.8 g, 38 mmol), 4,4,4′,4′,5,5,5′,5′-octamethyl-2,2′-bi(l,3,2-dioxaborolane) (9.6 g, 38 mmol), and potassium acetate (11 g, 110 mmol) in dioxane (200 rriL) was degassed and then added [1,1 ‘- bis(diphenylphosphino)ferrocene]dichloropalladium(II) (1.4 g, 1.9 mmol). The resulting mixture was stirred and heated at 80 C under nitrogen atmosphere for 15 h. Additional ore 4,4,4′,4′,5,5,5′,5′-octamethyl-2,2’-bi(l,3,2-dioxaborolane) (1.9 g, 7.6 mmol) was added and the reaction mixture was heated for another 3 h. the reaction mixture was cooled to room temperature and the mixture was diluted with dichloromethane and filtered through a pad of diatomaceous earth. The filtrate was concentrated at reduced pressure and purified by silica gel chromatography with a gradient from 0%-10% methanol in dichloromethane to afford the desired product as brown solid (9.5 g, 90% yield). LC-MS (acidic method) ret.time= 0.42 min, M+H = 198.1 (LC-MS acidic method).

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 3-amino-6-bromopyrazine-2-carboxylate, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; NOVARTIS AG; LUZZIO, Michael Joseph; PAPILLON, Julien; VISSER, Michael Scott; (213 pag.)WO2016/20864; (2016); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem