Tag: M.W=100-200

123-32-0, Name is 2,5-Dimethylpyrazine, 123-32-0, 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.

To the ethyl acetate solution (7 ml) of 2,5-dimethylpyrazine (500 mg, 5.36 mmol) at room temperature, m-chloroperbenzoic acid (1.27 g, 7.36 mmol) was added and stirred for 24 hours did. Thereafter, the reaction system was filtered and the solid was washed with ethyl acetate to obtain 2,5-dimethylpyrazine-N, N’-dioxide. Yield 517 mg, yield 80%, white solid

Statistics shows that 2,5-Dimethylpyrazine is playing an increasingly important role. we look forward to future research findings about 123-32-0.

Reference:
Patent; NIPPON STEEL & SUMIKIN CHEMICAL COMPANY LIMITED; KYUSHU INSTITUTE OF TECHNOLOGY; NAGAHAMA, TAKUO; KAWADA, ATSUSHI; TAKASHIMA, WATARU; OKAUCHI, TATSUO; NAGAMATSU, SHUICHI; (69 pag.)JP2017/178911; (2017); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

15707-23-0, 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 15707-23-0 as follows.

Ag2O (23.2 mg, 0.1 mmol), 3-nitro-1,2-benzenedicarboxylicacid (H2npt) (42.2 mg, 0.2 mmol) and epyz (24.4 mg, 0.2 mmol) were dissolved in methanol-H2O-DMF mixed solvent (6 mL,v/v/v = 1/1/1) in the presence of ammonia (0.5 mL, 14 M) underultrasonic treatment (160 W, 40 kHz, 30 min) under 40 C. Theresultant colorless solution was allowed slowly to evaporate atroom temperature in the dark. After several days, colorless platecrystals of 1 were isolated in about a 43% yield. They were washedwith a small volume of cold ethanol. Anal. Calc. for Ag2C15H13N3O6:C, 32.94; H, 2.40; N, 7.68. Found: C, 32.98; H, 2.38; N, 7.72%. IR(KBr): m (cm1) = 3440 (m), 3088 (w),3046 (w), 2976 (m),2932(w), 2876 (w), 1590 (s), 1520 (s), 1457(s), 1408 (s), 1344 (s),1288 (m), 1162 (m), 1027 (w), 929 (m), 859 (m), 824 (m), 782(w), 747 (w), 704 (m), 683 (m), 586 (w).

According to the analysis of related databases, 2-Ethyl-3-methylpyrazine, the application of this compound in the production field has become more and more popular.

Reference:
Article; Zhang, Ting; Wang, Dan-Feng; Huang, Rong-Bin; Zheng, Lan-Sun; Inorganica Chimica Acta; vol. 427; (2015); p. 299 – 304;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

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. 36070-80-1 name is 5-Chloropyrazine-2-carboxylic acid, 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. 36070-80-1

General procedure: The corresponding substituted salicylanilide 2 (1 mmol) and 5-chloropyrazine-2-carboxylic acid 1 (1 mmol) were dissolved in dryDMF (8 mL), the solution was cooled to 10 C and DCC (1.2 mmol)was added in three portions during 1 h. The mixture was stirred foradditional 3 h at the same temperature and then stored at 4 C for20 h. The precipitate of N,N0-dicyclohexylurea was removed byfiltration and the solvent was evaporated in vacuo till dryness. Thecrude products 3 were purified by one or repeated crystallizationfrom ethyl acetateehexane mixture.

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

Reference:
Article; Baranyai, Zsuzsa; Kratky, Martin; Vin?ova, Jarmila; Szabo, Nora; Senoner, Zsuzsanna; Horvati, Kata; Stola?ikova, Ji?ina; David, Sandor; Bosze, Szilvia; European Journal of Medicinal Chemistry; vol. 101; (2015); p. 692 – 704;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

875781-43-4, A common heterocyclic compound, 875781-43-4, name is 2-Bromo-5H-pyrrolo[2,3-b]pyrazine, molecular formula is C6H4BrN3, 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.

Preparation of 2-bromo-7-iodo-5H-pyrr lo [3,2-6] yrazine (Intermediate AT)[0316] To a solution of 2-bromo-5H-pyrrolo[3,2-?]pyrazine [Intermediate AS] (0.68 g, 3.4 mmol) in acetone (17 mL) was added N-iodosuccinimide (0.82 g, 3.6 mmol) and the resulting mixture was stirred for 4 h at rt. The mixture was evaporated in vacuo to yield a residue that was purified via silica gel chromatography eluting with 40% THF in hexanes to give the title compound as a yellow solid (0.99 g, 89%). 1H NMR (DMSO-dtf, 300 MHz): delta 12.82 (s, 1H), 8.42 (s, 1 H), 8.20 (s, 1 H). HPLC retention time: 2.23 minutes. MS ESI (m/z): 324.0, 326.0 (M+H)+, calc. 323.

The synthetic route of 875781-43-4 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; UNIVERSITY OF ROCHESTER; GELBARD, Harris, A.; DEWHURST, Stephen; GOODFELLOW, Val, S.; WIEMANN, Torsten; RAVULA, Satheesh, Babu; LOWETH, Colin, J.; WO2011/149950; (2011); A2;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

6164-79-0, Name is Methyl 2-pyrazinecarboxylate, 6164-79-0, 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.

d Pyrazine-2-hydrazide To a solution of the product from Example 1 step c) (22 g, 159 mmol) in methanol (250 ml) was slowly added hydrazine monhydrate (36.6 ml, 710 mmol). The reaction mixture was stirred for 1.5 h. The precipitate produced was filtered, washed with diethyl ether and dried in the oven at 80 C. to give the required product (30 g). 1H NMR (250 MHz, DMSO) delta 4.66 (2H, broad peak), 8.66 (1H, m), 8.84 (1H, d, J=2.5 Hz), 9.13 (1H, d, J=2.5 Hz), 10.15 (1H, broad peak); MS (ES+) m/e 139 [MH+].

Statistics shows that Methyl 2-pyrazinecarboxylate is playing an increasingly important role. we look forward to future research findings about 6164-79-0.

Reference:
Patent; Merck Sharp & Dohme Ltd.; US6297235; (2001); B1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

98-97-5, Adding a certain compound to certain chemical reactions, such as: 98-97-5, name is Pyrazine-2-carboxylic acid, 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 98-97-5.

(a) 2-pyrazine carboxylic acid, 104.3 gm, and 105.9 gm thionyl chloride were added to 800 ml methylene chloride and 5 ml dimethylformamide. The system was heated to reflux, at which point gas evolution took place. The system was stirred at reflux until gas evolution ceased, after about 5 hours, to give the 2-pyrazine carboxylic acid chloride. The solution was cooled to room temperature and transferred to a dropping funnel for use in Step (b) without further isolation.

According to the analysis of related databases, 98-97-5, the application of this compound in the production field has become more and more popular.

Reference:
Patent; Chevron Research Company; US4504484; (1985); A;; ; Patent; Chevron Research Company; US4588735; (1986); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

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.

In a sealed tube, Intermediate 30 (0.58 g, 1.079 mmol) was dissolved in DMF (5.39 mL). To the resulting solution was added 5-chloropyrazine-2-carboxylic acid (0.188 g, 1.187 mmol), HATU (0.615 g, 1.618 mmol), and pyridine (0.262 mL, 3.24 mmol). The reaction was stirred at 20 C. for 2 hours. The reaction was extracted into ethyl acetate, washed once with water, once with brine, dried with sodium sulfate, filtered through a fritted funnel, and concentrated. The crude material was eluted through a silica gel column using 0-50% EtOAc/Heptane. The desired fractions were combined and concentrated to yield tert-butyl N-[(4aR,6S,11bR)-10-[(5-chloropyrazine-2-carbonyl)amino]-3,3,6,11b-tetramethyl-4,4-dioxo-5,6-dihydro-4-aH-[1]benzoxepino[4,5-b][1,4]thiazin-2-yl]-N-tert-butoxycarbonyl-carbamate (0.640 g, 0.944 mmol, 87% yield) as an off-white solid.

According to the analysis of related databases, 5-Chloropyrazine-2-carboxylic acid, the application of this compound in the production field has become more and more popular.

Reference:
Patent; WHITE, Ryan; ALLEN, Jennifer R.; EPSTEIN, Oleg; HONG, Fang-Tsao; HUA, Zihao; HUMAN, Jason Brooks; LOPEZ, Patricia; OLIVIERI, Philip R.; ROMERO, Karina; SCHENKEL, Laurie; STELLWAGEN, John; TAMAYO, Nuria A.; ZHENG, Xiao Mei; US2014/213581; (2014); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding some certain compound to certain chemical reactions, such as: 486460-21-3, name is 3-(Trifluoromethyl)-5,6,7,8-tetrahydro-[1,2,4]triazolo[4,3-a]pyrazine, 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 486460-21-3. 486460-21-3

((c/s-1-(3-Chlorophenyl)-4-f3-(trifluoromethyl)-5.6-dihvdrori.2.4ltriazolof4.3-a1pyrazin- 7(8H)-yl1cvclohexyl)methyl)-carbamic acid tert-butyl ester and ((^ra/7s-1-(3-chlorophenyl)-4- f3-(triflupsilonoromethyl)-5.6-dihvdrof1.2.41triazolof4.3-a1pyrazin-7(8H)-vncvclohexyl>methyl)- carbamic acid tert-butyl esterSodium triacetoxyborohydride (316mg, 1.49mmol) was added to a solution of [1-(3- chlorophenyl)-4-oxo-cyclohexylmethyl]-carbamic acid tert-butyl ester (360mg, 1.07mmol) and 3-trifluoromethyl-5,6,7,8-tetrahydro-[1 ,2,4]triazolo[4,3-a]pyrazine (286.4mg, 1.49mmol) in 1 ,2-dichloroethane and the mixture was stirred at room temperature for 24h. The reaction was quenched with water and the product was extracted with ethyl acetate. The organic extracts were washed with brine, dried and concentrated in vacuo to give a yellow oil. The oil was purified by flash chromatography (silica, eluting with 1 :33:66 2M ammonia in methanol:ethyl acetatexyclohexane) to afford the individual title compounds as white solids.Cis diastereoisomer:MS (ES+): 514[M+H]+.TR [HPLC, Phenomenex Luna 3 micron C18; 5-95% CH3CN+0.1%Formic acid/H2O+0.1%Formic acid for 5 min, flow 2.0 ml/min]: 3.70 min.Trans diastereoisomer:MS (ES+): 514[M+H]TR [HPLC, Phenomenex Luna 3 micron C18; 5-95% CH3CN+0.1%Formic acid/H2O+0.1%Formic acid for 5 min, flow 2.0 ml/min]: 3.57min

Chemical properties determine the actual use. Each compound has specific chemical properties and uses. We look forward to more synthetic routes in the future to expand reaction routes of 3-(Trifluoromethyl)-5,6,7,8-tetrahydro-[1,2,4]triazolo[4,3-a]pyrazine.

Reference:
Patent; NOVARTIS AG; WO2008/77597; (2008); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding some certain compound to certain chemical reactions, such as: 95-58-9, name is 2-Chloro-3-methylpyrazine, 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 95-58-9. 95-58-9

Compound 1 (500 g, 1.92 mol) and aqueous ammonia (5.5 L) were placed in a 10 L autoclave and reacted at 160 C for 24 hours. TLC or LCMS showed the reaction was completed.The reaction was cooled and filtered to give a white solid, the remaining reaction solution was extracted with ethyl acetate (1.5 L x 5), the extracts were combined, dried over anhydrous sodium sulfate,The resulting white solid was concentrated under reduced pressure and combined with the filtered solid which was dried in vacuo to give crude compound 2 (420 g).

Chemical properties determine the actual use. Each compound has specific chemical properties and uses. We look forward to more synthetic routes in the future to expand reaction routes of 2-Chloro-3-methylpyrazine.

Reference:
Patent; Shanghai He Quan Pharmaceutical Co., Ltd.; Shanghai He Quan Pharmaceutical Research And Development Co., Ltd.; Changzhou Hequan Pharmaceutical Co., Ltd.; Changzhou Hequan Drug Discovery Co., Ltd.; Wuxi Yaoming Kant, Immanuel Pharmaceutical Co., Ltd.; Wuxi Yaoming Kant, Immanuel Bio-technology Co., Ltd.; Mao Yanjun; Tang Xiaowu; Guo Zemin; He Mina; Jiang Xinxin; Bao Weize; Wu Dongping; Yuan Chaowei; Li Hong; Yu Lingbo; Ma Rujian; (5 pag.)CN107312007; (2017); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

20737-42-2, 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. 20737-42-2, name is 3-Oxo-3,4-dihydropyrazine-2-carboxylic acid, This compound has unique chemical properties. The synthetic route is as follows.

Example 6. Production of N-{3-isobutyl-4-[2,2,2-trifluoro-1-(trifluoromethyl)ethyl]pheny}-3-chloropyrazine-2-carboxamide (compound No. 1-25) 3-Hydroxypyrazine-2-carboxylic acid (154 mg, 1.1 mmol) was dissolved in phosphorus oxychloride (2 ml), followed by adding one drop of pyridine, refluxing under heating for 2 hours. After that, the reaction solution was concentrated under reduced pressure to obtain 3-chloropyrazine-2-carboxylic acid chloride. The compound was added to a tetrahydrofuran solution (10 ml) of 3-isobutyl-4-[2,2,2-trifluoro-1-(trifluoromethyl)ethyl]aniline (299 mg, 1 mmol) and triethylamine (303 mg, 3 mmol) and refluxed under heating for 3 hours. The reaction solution was diluted with ethyl acetate, followed by washing with water. The organic layer was dried over magnesium sulfate anhydride, and concentrated under reduced pressure, and then the residue was purified by using silica gel chromatography (hexane:ethyl acetate=2:1) to obtain 200 mg of the desired compound. Yield: 46% Property: Melting point 128 to 129C

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; NIHON NOHYAKU CO., LTD.; EP1757595; (2007); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem