Tag: M.W=100-200

These common heterocyclic compound, 122-05-4, name is Pyrazine-2,5-dicarboxylic acid, 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. Quality Control of Pyrazine-2,5-dicarboxylic acid

Dimethyl Pyrazine-2,5-dicarboxylate (83). Hydrogen chloride gas was bubbled (approx. 5 min) into a stirred suspension of 82 (0.5 g, 2.97 mmol) in methanol (25 ml) and the mixture refluxed for 4 hours. Solvent was evaporated under reduced pressure and the residual solid dissolved in chloroform. The chloroform solution was washed with 10% sodium carbonate solution and water, dried (MgSO4) and evaporated under reduced pressure. Solid obtained was recrystallized from methanol to afford 0.42 g (72.2%) of colorless needles mp 167-169 C. [lit. Spoerri, P. E. and Erickson, A. J. Amer. Chem. Soc. 1938, 60, 400-402, mp 168-169 C. (sealed capillary)]; IR (KBr) cm-1 1720 (ester); NMR (CDCl3, 90 MHz) delta 4.09 (s, 6H, CO2 CH3), 9.40 (s, 2H, aromatic). Anal. calcd. for C8 H8 N2 O4: C, 48.98; H, 4.11; N, 14.28. Found: C, 48.89; H, 4.33; N, 14.12.

The synthetic route of Pyrazine-2,5-dicarboxylic acid has been constantly updated, and we look forward to future research findings.

Reference:
Patent; The Ohio State University; US4871736; (1989); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 356783-16-9, The chemical industry reduces the impact on the environment during synthesis 356783-16-9, name is 3,6-Dichloropyrazine-2-carbonitrile, I believe this compound will play a more active role in future production and life.

To a solution of 3,6-dichloropyrazine-2-carbonitrile (1.088 g, 6.25 mmol) in toluene (12 mL) at 0 C. was added dropwise methyl hydrazine (362 muL, 6.88 mmol). Reaction mixture was stirred for 3 hours at 0 C. LCMS shows no starting material. Reaction mixture was concentrated and purified by CombiFlash (120 g Gold, 10-45% EtOAc/Hex) to give impure product. Crystallized from hot acetone/hexane to give two crops of 5-chloro-1-methyl-1H-pyrazolo[3,4-b]pyrazin-3-amine. LCMS-ESI+: calc’d for C6H7ClN5: 184.0 (M+H)+; found: 184.2 (M+H)+.

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, 3,6-Dichloropyrazine-2-carbonitrile, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; Gilead Sciences, Inc.; Cai, Zhenhong R.; Guo, Hongyan; Ji, Mingzhe; Jin, Haolun; Lee, Amy; McFadden, Ryan; Mitchell, Michael L.; Munoz, Manuel; Pyun, Hyung-Jung; Xu, Lianhong; Yang, Hong; (272 pag.)US2018/118734; (2018); A1;,
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. 6863-73-6, name is 3-Chloropyrazin-2-amine, This compound has unique chemical properties. The synthetic route is as follows., Formula: C4H4ClN3

Example A3 8-Chloro-imidazo[1,2-a]pyrazine Bromoacetaldehyde diethyl acetal (17.4 ml, 115.8 mmol) was added dropwise to a 48% aqueous solution of hydrobromic acid (4.45 ml, 38.6 mmol) at RT. The mixture was stirred at reflux temperature for 2 h. and then poured onto a suspension of sodium hydrogen carbonate (74.5 g, 0.88 mol) in isopropanol (220 ml). The mixture was stirred for a further 30 min. and then filtered off. 3-Chloro-pyrazin-2-ylamine (5 g, 38.6 mmol) was added to the filtrate and the mixture was stirred at 85 C. for 4 h. The solvent was evaporated in vacuo and the crude product suspended in a saturated solution of sodium hydrogen carbonate and extracted with DCM. The organic layer was dried (Na2SO4), filtered and the solvents evaporated in vacuo. The crude product was precipitated from Et2O to yield intermediate 3 (4.1 g, 70%) as a brown solid which was used in the next step without further purification.

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 6863-73-6.

Reference:
Patent; Janssen Pharmaceutica NV; US2012/329792; (2012); A1;,
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. 33332-25-1, name is Methyl 5-chloropyrazine-2-carboxylate, This compound has unique chemical properties. The synthetic route is as follows., Computed Properties of C6H5ClN2O2

Preparative Example 1. EPO A round bottomed flask was charged with methyl 2-chloropyrazine-5-carboxylate (Lonza, 25.9 g, 145 mmol), 2-S-ethyl piperazine (prepared as per Williams et al J. Med. Chem 1996, 39, 1345, 85% active, 28.0 g, 208 mmol), cesium carbonate (Aldrich, 11O g, 338 mmol) and 1 ,4 dioxane (400 ml). The resulting suspension was stirred at room temperature for 18 hours and then filtered. The solid was washed with ethyl acetate (3X400 ml). The combined organic solutions were concentrated on a rotary evaporator to remove the solvent. The residue was purified by flash chromatography on silica gel using 5% to 10% methanol in dichloromethane as an eluent to provide A3 as a white solid (28.0 g, 77%).

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 33332-25-1.

Reference:
Patent; SCHERING CORPORATION; PHARMACOPEIA DRUG DISCOVERY, INC.; WO2006/88837; (2006); A2;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 768-05-8,Some common heterocyclic compound, 768-05-8, name is Pyrazinoic acid hydrazide, molecular formula is C5H6N4O, 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.

2-Hydroxyacetophenone (0.1g; 0.73mmol), hydrazide 3c (0.1g; 0.73mmol) and acetic acid (0.20mL) were dissolved in methanol (5mL) and heated at 110C in an autoclave for 24h. After cooling to rt, the solid was filtered off, washed with methanol and dried over P2O5. The filtrate was diluted with water and left to crystallize at 4C for 24h. A second load of solid was filtered off, washed with water and methanol and dried over P2O5. The overall yield of yellow solid was 0.14g (74%; lit [37]. 63%). Rf=0.88 (CHCl3/MeOH 20:1). mp 237-239C. IR (KBr): numax, 3347; 1690; 1508; 1489; 1250; 1157; 1043; 1021cm-1. 1H NMR (300MHz, DMSO) delta 13.03 (s, 1H, OH), 11.53 (s, 1H, NH), 9.25 (s, 1H, Ar), 8.96-8.87 (m, 1H, Ar), 8.84-8.68 (m, 1H, Ar), 7.64 (dd, J=8.1, 1.5Hz, 1H, Ar), 7.43-7,16 (m, 1H, Ar), 7.02-6.73 (m, 2H, Ar), 2.46 (s, 3H, CH3). 13C NMR (75MHz, DMSO): delta 160.9, 160.4, 159.2, 148.5, 144.7, 144.6, 144.0, 132.2, 129.3, 119.6, 119.2, 117.8, 14.4. Anal. Calcd. for C13H12N4O2: C, 60.93; H, 4.72; N, 21.86; Found: C, 61.27; H, 4.83; N, 21.76.

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

Reference:
Article; Hru?kova, Kate?ina; Pot??kova, Eli?ka; Hergeselova, Tereza; Liptakova, Lucie; Ha?kova, Pavlina; Mingas, Panagiotis; Kova?ikova, Petra; ?im?nek, Toma?; Vavrova, Kate?ina; European Journal of Medicinal Chemistry; vol. 120; (2016); p. 97 – 110;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 59303-10-5, name is 2-Chloro-5-methylpyrazine, 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 59303-10-5, Safety of 2-Chloro-5-methylpyrazine

To a solution of rac- I -((2S,3R,4R)-4-amino-2-ethyl-3-methyl-6-morpholino-3,4-dihydroqu inolin1(2H)-yl)ethanone (for a preparation see Intermediate 73, 50 mg, 0.158 mmol) in 1,4-dioxane (1.5 ml) was added tris(dibenzylideneacetone)dipalladium(0) (28.8 mg, 0.032 mmol), Davephos (12.40mg, 0.032 mmol), sodium tert-butoxide (30.3 mg, 0.315 mmol) and 2-chloro-5-methylpyrazine (40.5 mg, 0.315 mmol). The reaction mixture was heated under microwave conditions, using initial normal absorption setting, to 120 C for 30 mm. The sample was diluted with ethyl acetate (5 mL) and loaded onto a celite cartridge (2.5 g). The cartridge was washed with further ethyl acetate (2×10 mL), and the combined fractions dried under a stream of nitrogen. The sample was dissolved in DMSO(2×1 mL) and purified by MDAP (HpH). The solvent was blown down under a stream of nitrogen to give the required product (14 mg) as a yellow gum. LCMS (2 mm HpH): Rt = 0.87 mi [MH] = 410.

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-Chloro-5-methylpyrazine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; GLAXOSMITHKLINE INTELLECTUAL PROPERTY (NO.2) LIMITED; AMANS, Dominique; ATKINSON, Stephen John; HARRISON, Lee Andrew; HIRST, David Jonathan; LAW, Robert Peter; LINDON, Matthew; PRESTON, Alexander; SEAL, Jonathan Thomas; WELLAWAY, Christopher Roland; WO2014/140076; (2014); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 5521-55-1, A common heterocyclic compound, 5521-55-1, name is 5-Methylpyrazine-2-carboxylic acid, molecular formula is C6H6N2O2, 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.

5-Methyl-pyrazine-2-carboxylic acid (691 mg, 5 mmol) was stirred in toluene (15 mL) and treated with TEA (765 mL, 5.5 mmol) followed by diphenylphosphoryl azide (1.0 mL, 5.0 mmol). The resulting solution was stirred for 30 min, then used directly.A solution of 5-methyl-pyrazine-2-carbonyl azide (1.0 mmol) in toluene was heated at 900C for 10 min. The reaction flask was removed from the heating bath and the brown solution was treated with 2- (1,4- dimethyl-piperazin-2-ylmethoxy) -5-methyl-phenylamine EPO (0.25 g, 1.0 iranol) . The flask was returned to the heating bath and heated at 40C for 4 h. The mixture was allowed to cool, then filtered to give the product as a tan powder. 1H-NMR (400 MHz, CDCl3) delta 10.90 (s, 1, H), 8.4 (s, 1, H), 8.2 (m, 3, H), 6.8 (m, 2, H), 4.2 (dd, 1, H), 3.9 (t, 1, H),.3.1 (d, 1, H), 2.8 (br d, 1, H), 2.6 (m, 2, H), 2.5 (s, 3, H), 2.4 (m, 1, H), 2.4 (s, 3, H), 2.3 (S, 3, H), 2.25 (m, 1, H), 2.2 (s, 3, H), 2.1 (m, 1, H). LRMS (esi, positive) m/e 385.30 (M+l) .

The synthetic route of 5521-55-1 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; ICOS CORPORATION; WO2006/105262; (2006); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

These common heterocyclic compound, 21279-62-9, name is 3-Chloropyrazine-2-carboxamide, 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. HPLC of Formula: C5H4ClN3O

General procedure: The starting compound (1.27 mmol) was treated with 18 aliphatic amines, alicyclic amines or saturated heterocycles containing at least one nitrogen atom (2.54 mmol). Four reactions were completed by conventional heating methods. The conditions were 110 C, toluene as a solvent and pyridine (1.27 mmol) as a base. The reaction time was set to one hour. Then the reactions were completed using the microwave reactor with focused field and conditions used for syntheses were 140 C, 30 min,120 W, methanol used as a solvent and pyridine (1.27 mmol) as a base. They were set experimentally with respect to prior experience. The progress of reaction was monitored with TLC in system hexane/ethyl acetate (1:1). Then the mixture was separated by flash column chromatograph using gradient elution. Mobile phases were hexane and ethyl acetate again.

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

Reference:
Article; Jandourek, Ondrej; Dolezal, Martin; Kunes, Jiri; Kubicek, Vladimir; Paterova, Pavla; Pesko, Matus; Buchta, Vladimir; Kralova, Katarina; Zitko, Jan; Molecules; vol. 19; 7; (2014); p. 9318 – 9338;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 59303-10-5, 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 59303-10-5 as follows.

A mixture of 2-chloro-5-methylpyrazine (300 mg, 1.6 mmol), (R)-tert-butyl 3-aminopyrrolidine-l- carboxylate (206 mg, 1.6 mmol), BINAP (199 mg, 0.3 mmol), Pd2(dba)3 (73 mg, 0.08 mmol) and t- BuONa (307 mg, 3.2 mmol) in toluene (10 mL) was stirred at 80C under N2 for 3 hours. The mixture was cooled to RT and concentrated. The residue was purified by reverse phase chromatography to afford (R)-tert-butyl 3-((5-methylpyrazin-2-yl)amino)pyrrolidine-l-carboxylate (240 mg, 54%) as yellow oil. [M+H] Calc?d for Ci4H22N402, 279.1; Found, 279.1.

According to the analysis of related databases, 59303-10-5, the application of this compound in the production field has become more and more popular.

Reference:
Patent; KINNATE BIOPHARMA INC.; KANOUNI, Toufike; ARNOLD, Lee D.; KALDOR, Stephen W.; MURPHY, Eric A.; TYHONAS, John; (0 pag.)WO2020/6497; (2020); 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. 109838-85-9, name is (R)-2-Isopropyl-3,6-dimethoxy-2,5-dihydropyrazine, A new synthetic method of this compound is introduced below., Application In Synthesis of (R)-2-Isopropyl-3,6-dimethoxy-2,5-dihydropyrazine

To a solution of (R)-2-isopropyl-3, 6-dimethoxy-2, 5-dihydropyrazine (500 mg, 2.72 mmol) and bis(chloromethyl) dimethylsilane (636 mg, 4.08 mmol) in THF (10 mL) under N2atmosphere in a dry ice/acetone bath was slowly n-BuLi (1.6 M in hexane, 2 mL, 3.2 mmol) via an injection syringe. After addition, the reaction was stirred at room temperature overnight. The reaction mixture was cooled to 0° C. and quenched by dropwise addition of water. The resulting mixture was extracted with EtOAc. The organic layer was washed by brine, dried over anhydrous Na2SO4and concentrated. The obtained crude product was purified by column chromatography on silica gel eluted with PE/EtOAc (100:1 to 30:1) to give the title compound (640 mg, 77.5percent yield); LC/MS (ESI) m/z: 305 [M+H]

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; ACHILLION PHARMACEUTICALS, INC.; WILES, Jason, Allan; PHADKE, Avinash, S.; DESHPANDE, Milind; AGARWAK, Atul; CHEN, Dawei; GADHACHANDA, Venkat, Rao; HASHIMOTO, Akihiro; PAIS, Godwin; WANG, Qiuping; WANG, Xiangzhu; (905 pag.)WO2017/35353; (2017); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem