Tag: M.W=100-200

Application of 36070-80-1,Some common heterocyclic compound, 36070-80-1, name is 5-Chloropyrazine-2-carboxylic acid, molecular formula is C5H3ClN2O2, 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.

The starting 5-chloropyrazine-2-carboxylic acid (317 mg, 2 mmol) was converted to5-aminopyrazine-2-carboxylic acid (1) by substitution reaction with 25% (m/m) aqueous solutionof ammonia (3 mL). The reaction was carried out 10 mL microwave pressurized vials with stirring(reaction temperature: 100 C, reaction time: 30 min, power output: 80 W). The reaction was repeated20 times to yield reasonable quantity of the starting acid. Once the reaction was completed, the vials content was put onto Petri dish and heated above a water bath with intermittent stirring until a drysolid was obtained (ammonium salt of the product). To get the free acid form, the ammonium salt wasdissolved in water and drop-wise acidified with 10% hydrochloric acid to reach pH of 4. The mixturewas then left to cool down in room temperature for 5 min then kept in the fridge for 15 min. The formedfree acid crystals were filtered off by filtration paper with suction and left to dry overnight. After itwas dried, the resulting 5-aminopyrazine-2-carboxylic acid (1) was esterified in several microwavepressurized vials; 3 mL of anhydrous propanol and 2 drops of concentrated sulfuric acid were added to278 mg (2 mmol) of compound 1 in each vial. The esterification was carried out in microwave reactor(reaction temperature: 100 C, reaction time: 1 h, power output: 80 W). The completion of reaction wasmonitored by TLC in system hexane/ethyl acetate (EtOAc) (1:3). The ester was then purified by flashchromatography using gradient elution 40 to 100% EtOAc in hexane.

The synthetic route of 36070-80-1 has been constantly updated, and we look forward to future research findings.

Reference:
Article; Bouz, Ghada; Juhas, Martin; Niklova, Pavlina; Jand?ourek, Ond?ej; Paterova, Pavla; Ek, Ji?i Janou; T?mova, Lenka; Kovalikova, Zuzana; Kastner, Petr; Dole al, Martin; Zitko, Jan; Molecules; vol. 22; 10; (2017);,
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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., Quality Control of Pyrazinoic acid hydrazide

General procedure: Acid hydrazides 18(a-j) (1.0 mmol)were dissolved in ethanol (50 mL),and to this potassiumhydroxide was added (1.49 mmol) which is dissolved inwater (2 mL), and then carbondisulfide was added(4.0 mmol). Then, the reaction mixture was heated at reflux for 10-12 h. Solvent was evaporated, and the residue wasacidified with 10 % HCl. The precipitate was collected byfiltration, washed with water and dried. The products 19(a-j) were used without further purification.

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

Reference:
Article; Murty; Penthala, Raju; Polepalli, Sowjanya; Jain; Medicinal Chemistry Research; vol. 25; 4; (2016); p. 627 – 643;,
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Adding a certain compound to certain chemical reactions, such as: 25911-65-3, name is 3-Aminopyrazine-2-carbonitrile, 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 25911-65-3, category: Pyrazines

a) 4-Amino-2-(benzyloxymethyl)pteridine Obtained using the procedure described in section c of Example 2, starting with 12.0 g (0.10 mole) of 3-amino-2-pyrazinecarbonitrile and 25.0 g (0.15 mole) of 2-(benxyloxy)acetamidine [prepared according to W. J. Haggerty Jr. and W. J. Rost, J. Pharm. Sci. 1969, 58, 50] in 400 ml of absolute ethanol. Refluxing time: 4 hours. Yld: 15.4 g (58%), m.p. 112-114 C. An analytical sample was obtained by recrystallization from ethanol, followed by washing with dilute hydrochloric acid and finally recrystallization from ethyl acetate. M.p. 131-133 C. NMR (DMSO-d6): delta=4.6 (2H, s); 4.7 (2H, s); 7.1-7.6 (5H, m); 8.3 (2H, peak exchangeable with CF3 COOD); 8.8 (1H, d); 9.0 (1H, d).

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-Aminopyrazine-2-carbonitrile, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; Lipha, Lyonnaise Industrielle Pharmaceutique; US5167949; (1992); A;,
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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. 889447-19-2, name is 2-Chloro-5H-pyrrolo[2,3-b]pyrazine, A new synthetic method of this compound is introduced below., HPLC of Formula: C6H4ClN3

2-Chloro-5H-pyrrolo[2,3-b]pyrazine (80 mg, 1.82 mmol) was dissolved in 2-methyltetrahydrofuran (10 mL), and NIS (451 mg, 2.00 mmol) was added thereto. The resulting reaction solution was allowed to react at room temperature overnight.The reaction was quenched by the addition of saturated sodium thiosulfate (50 mL).The aqueous phase was extracted with ethyl acetate (50 mL X 2).The combined organic phases were washed with brine (80 mL).Dry over anhydrous sodium sulfate, filter, and dilute the solvent under reduced pressure.The residue was purified by silica gel column chromatography(petroleum ether/ethyl acetate (nu/nu) = 20/1-4/1),The title compound was obtained as a yellow solid ( 456 g, 89%).

The synthetic route of 889447-19-2 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Guangdong Dongyangguang Pharmaceutical Co., Ltd.; Ren Qingyun; Tang Changhua; Yin Junjun; Wang Yejun; Yi Kai; Lei Yibo; Zhang Yingjun; S ·geerdeman; Yan Huan; Nie Biao; Xu Juan; Chen Jianping; Chen Yunfu; Zhang Weihong; Cheng Lijun; Ye Weiliang; (197 pag.)CN110117285; (2019); A;,
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Synthetic Route of 6164-79-0, The chemical industry reduces the impact on the environment during synthesis 6164-79-0, name is Methyl 2-pyrazinecarboxylate, I believe this compound will play a more active role in future production and life.

(1) Pyrazine-2-carboxylic acid is fully dissolved in anhydrous methanol,Then add an appropriate amount of concentrated sulfuric acid and heat to reflux for 5 h.After the reaction is cooled, adjust the pH to neutral with saturated NaHCO3,Extract with dichloromethane and keep the dichloromethane layer,The solvent was removed by rotary evaporation to obtain an oily pyrazine-2-carboxylic acid methyl ester;After dissolving it in anhydrous methanol, hydrazine hydrate was added dropwise, and after heating under reflux for 21 h,Cool to room temperature, remove methanol by rotary evaporation to obtain pyrazine-2-hydrazide as a red solid product;The ratio of the amount of pyrazine-2-carboxylic acid methyl ester to the amount of hydrazine hydrate is 1: 2.

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 2-pyrazinecarboxylate, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; Tianjin Medical University; Xu Jingyuan; Wang Zhigang; Xie Chengzhi; (13 pag.)CN110372681; (2019); A;,
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Synthetic Route of 4858-85-9, The chemical industry reduces the impact on the environment during synthesis 4858-85-9, name is 2,3-Dichloropyrazine, I believe this compound will play a more active role in future production and life.

1H-indole-6-carboxylic acid, 3-cyclohexyl-2-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-, methyl ester (383 mg, 1.0 mmol), 2,3-dichloropyrazine (298 mg, 2.0 mmol) and LiCl (84 mg, 2.0 mmol) were dissolved in a mixture of ethanol (4 mL) and toluene (4 mL). An aqueous Na2CO3 solution (1M, 2.5 mL, 2.5 mmol) was added and the mixture was degassed with nitrogen for 20 min. Pd(PPh3)4 (11.5 mg, 0.1 mmol) was added and the mixture was stirred at 60 C. under N2 for 20 h. EtOAc (10 mL) was added, followed by 25 mL of water. The organic layer was separated, dried (Na2SO4), filtered and evaporated under reduced pressure to give a residue. This material was fractionated using flash chromatography on silica gel (CH2Cl2-EtOAc 10:1) to afford 160 mg (43%) of the title compound as a foam. 1H NMR (500 MHz, CDCl3) delta 1.20-2.00 (m, 10H), 2.88 (m, 1H), 3.94 (s, 3H), 7.79 (dd, 1H, J=1.5, 8.5), 7.91 (d, 1H, J=8.5), 8.14 (d, 1H, J=-1.5), 8.41 (d, 1H, J=2.5), 8.60 (br s, 1H, NH), 8.63 (d, 1H, J=2.5).

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, 2,3-Dichloropyrazine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; Hudyma, Thomas W.; Zheng, Xiaofan; He, Feng; Ding, Min; Bergstrom, Carl P.; Hewawasam, Piyasena; Martin, Scott W.; Gentles, Robert G.; US2006/46983; (2006); A1;,
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Adding a certain compound to certain chemical reactions, such as: 33332-28-4, name is 2-Amino-6-chloropyrazine, 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 33332-28-4, Application In Synthesis of 2-Amino-6-chloropyrazine

A solution of 6-chloropyrazin-2-amine (10.0 g, 77 mmol) in DMSO (100 ml) was treated with 1-iodopyrrolidine-2,5-dione (20.84 g, 93 mmol). The reaction mixture was stirred at RT for 2 days and then added to water (800 ml). The pH was adjusted to pH 8-9 using a sat. NaHCO3 solution and the resulting suspension was filtered, washing with water (*3) and dried under vacuum to afford the titled compound as an orange solid; LC-MS Rt=0.83 mins; [MeCN+H]+ 296.0, Method 2 minLowpH.

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, 2-Amino-6-chloropyrazine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; NOVARTIS AG; Adcock, Claire; Leblanc, Catherine; US2013/184282; (2013); A1;,
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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. HPLC of Formula: C5H7ClN4

A mixture of diethyl 2-(2,4,6-trifluorophenyl)malonate (U.S. Pat. No. 6,156,925) (870 mg, 3.0 mmol), 2-pyrazinecarboxamidine hydrochloride (500 mg, 3.15 mmol), and 600 mg of tributylamine is stirred under nitrogen atmosphere at 180 C. for 1 h and cooled to room temperature. The mixture is cooled to room temperature and treated with 1.0 N hydrochloric acid. The precipitates are collected by filtration, washed with water and dried to give 2-pyrazin-2-yl-5-(2,4,6-trifluorophenyl)pyrimidine-4,6-diol as a tan solid (401 mg), which is used directly in the next step.

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

Reference:
Patent; Wyeth; US2005/75357; (2005); A1;,
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Electric Literature of 36070-80-1, 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 36070-80-1 as follows.

[00778] To a solution of lenalidomide (0.2g, 0.77 mmol) in DMF (4 mL) was added 5-chloropyrazine-2-carboxylic acid (0.15g, 0.95 mmol), HATU, (0.29g, 0.77 mmol), and DIPEA (0.27mL, 1.54 mmol). The reaction was stirred at room temperature for 1 hr before it was quenched with saturated NH4C1 (5 mL). The mixture was extracted with EtOAc (10 mLx3), and the combined organic phase was dried over Na2SO4 and concentrated. Column chromatography gave 5-chloro-N-(2- (2,6-dioxopiperidin-3-yl)- 1 -oxoisoindolin-4-yl)pyrazine-2-carboxamide (0.1 g, 33%).

According to the analysis of related databases, 36070-80-1, the application of this compound in the production field has become more and more popular.

Reference:
Patent; SYNTA PHARMACEUTICALS CORP.; CHIMMANAMADA, Dinesh, U.; YING, Weiwen; WO2013/158644; (2013); A2;,
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Electric Literature of 54013-06-8, 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. 54013-06-8, name is Ethyl 5-aminopyrazine-2-carboxylate belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below.

Example 3 5-{[(6-Bromo-3-methyl-2-phenylquinolin-4-yl)carbonyl]amino}pyrazine-2-carboxylic acid (0773) (0774) 100 mg (0.26 mmol) of the compound from example 2A and 43 mg (0.26 mmol) of 377 ethyl 5-aminopyrazine-2-carboxylate were dissolved in 2 ml of 49 DMF. 72 mg (0.64 mmol) of 153 potassium tert-butoxide were added in portions to the solution. The reaction mixture was stirred at RT overnight, and then 1.3 ml (1.3 mmol) of 1 M 196 sodium hydroxide solution were added. After stirring at 80 C. for 1 h and cooling to RT, the mixture was adjusted to pH 1-2 with 1 M hydrochloric acid. The mixture was extracted with ethyl acetate, and the organic phase was removed and washed with saturated sodium chloride solution. After the organic phase had been dried over sodium sulfate and the solvent had been removed on a rotary evaporator, the residue was taken up in a little DMF and purified by means of preparative HPLC (method 6). After the solvent-water mixture had been removed, the residue was taken up in a little acetonitrile, water was added and then the mixture was lyophilized. Since solvent residues were still present, the lyophilizate was redissolved in 124 dichloromethane and 61 ethyl acetate, 43 water was added again and the mixture was lyophilized again. The resulting lyophilizate was redissolved once again in dichloromethane and 378 tert-butanol, water was added and the mixture was lyophilized again. The lyophilizate thus obtained was dried at 100 C. under high vacuum for a total 9 h. In this way, 39 mg (29% of theory, 90% purity) of the 379 title compound were obtained. (0775) 1H-NMR (600 MHz, DMSO-d6): delta [ppm]=13.54 (br. s, 1H), 12.03 (s, 1H), 9.71 (s, 1H), 9.01 (s, 1H), 8.10 (d, 1H), 8.04 (d, 1H), 7.93 (dd, 1H), 7.66-7.60 (m, 2H), 7.58-7.50 (m, 3H), 2.41 (s, 3H). (0776) LC/MS (Method 1, ESIpos): Rt=0.96 min, m/z=463/465 [M+H]+.

The synthetic route of Ethyl 5-aminopyrazine-2-carboxylate has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Bayer Pharma Aktiengesekkschaft; BECK, Hartmut; THALER, Tobias; KAST, Raimund; MEIBOM, Daniel; MEININGHAUS, Mark; TERJUNG, Carsten; DELBECK, Martina; LUSTIG, Klemens; MUENSTER, Uwe; OLENIK, Britta; (100 pag.)US2017/260140; (2017); A1;,
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