Tag: M.W=100-200

Application of 5521-55-1, 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. 5521-55-1 name is 5-Methylpyrazine-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.

To a flask fitted with overhead stirrer, condenser, thermometer and nitrogen line was added 5-methylpyrazine-2-carboxylic acid (1.0 eq), tert-butanol (3.5 vols) and di-isopropylethylamine (1.5 eq) under a nitrogen atmosphere. The mixture was heated to 82 C., then diphenylphosphorylazide (1.0 eq) was added over a time period of 5-14 hours, maintaining the temperature of the reaction mixture at approximately 82 C. The reaction mixture was stirred for at least 1.5 hours, and then cooled to approximately 60 C. A solution of 4% w/w sodium hydroxide (1.75 eq) was added over a period of 2 hours. The mixture was cooled to 15 C. over at least 5 hours then held at 15 C. for 3 hours. The batch was then filtered, and the solid slurry washed with water (2 vols). The batch was again slurry washed with water (2 vols). After drying at 55-60 C. overnight, the desired product was obtained as a solid (corrected yield 56-63%). 1H NMR delta (400 MHz CDCl3): 9.18 (s, 1H), 8.17 (bs, 1H), 8.11 (s, 1H), 2.51 (s, 3H), 1.56 (s, 9H)

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

Reference:
Patent; AstraZeneca AB; US2010/210841; (2010); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

33332-28-4, name is 2-Amino-6-chloropyrazine, 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. COA of Formula: C4H4ClN3

Example 1C 6-(3-butenyloxy)-2-pyrazinamine A suspension of NaH (60percent, 618 mg, 15.45 mmol) in dioxane (30 mL) at 0° C. was treated with 3-buten-1-ol (1.33 mL, 15.45 mmol), stirred for 2 hours, treated with 2-amino-6-chloropyrazine (1 g, 7.72 mmol), stirred at 100° C. for 2.5 days, cooled to room temperature, and diluted with ethyl acetate. The mixture was washed with water, dried (MgSO4), filtered, and concentrated. The concentrate was purified by flash column chromatography eluding with hexanes/ethyl acetate (2:1) to provide the desired product (390 mg, 31percent). MS (DCI/NH3) m/z 166.12 (M+H)+; 1H NMR (500 MHz, benzene-d6) delta 2.66 (m, 2H), 4.42 (t, J=6.87 Hz, 2H), 5.24 (dd, J=10.22, 1.98 Hz, 1H), 5.30 (m, 1H), 6.04 (m, 1H), 7.64 (s, 1H), 7.65 (s, 1H).

The synthetic route of 33332-28-4 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Lin, Nan-Horng; Li, Gaoquan; Przytulinska, Magdalenna K.; Sowin, Thomas J.; Sullivan, Gerard M.; Tao, Zhi-Fu; Tong, Yunsong; Wang, Le; US2005/215556; (2005); 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. 875781-43-4, name is 2-Bromo-5H-pyrrolo[2,3-b]pyrazine, A new synthetic method of this compound is introduced below., Recommanded Product: 875781-43-4

General procedure: 2-Bromo-5H-pyrrolo[3,2-b]pyrazine(4; 0.471 g,2.39 mmol), 4-pyridylboronic acid (0.58 g, 4.72 mmol), dichloro 1,1′-bis(diphenylphosphino)ferrocenepalladium (II) dichloromethane adduct (0.097 g, 0.12 mmol), acetonitrile(3 mL) and 1M sodium carbonate (3 mL) were placed in a 10 mL CEM microwavevial. The vial was capped and irradiated in a CEM microwave reactor for 30minutes at 150 C.Water (3 mL) and ethyl acetate (9 mL) were added the layers were partitioned. Theaqueous layer was extracted with ethyl acetate (2 x 10 mL). The combined organicextracts were washed with saturated sodium chloride (5 mL), dried over MgSO4and concentrated under reduced pressure. The residue was purified by preparativereverse phase HPLC to give 2-(pyridin-4-yl)-5H-pyrrolo[2,3-b]pyrazine(14; 0.28 g,60%) as an off white solid: 1H NMR (400 MHz, DMSO-d6) delta 12.24 (s, 1H), 9.00(s, 1H), 8.69 (dd, J = 4.5, 1.6 Hz, 2H), 8.12 (dd, J = 4.5, 1.6Hz, 2H), 7.98 (d, J = 3.6 Hz, 1H), 6.74 (d, J = 3.6 Hz, 1H); ESMSm/z 197.1 (M+1).

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:
Article; Burdick, Daniel J.; Wang, Shumei; Heise, Christopher; Pan, Borlan; Drummond, Jake; Yin, Jianping; Goeser, Lauren; Magnuson, Steven; Blaney, Jeff; Moffat, John; Wang, Weiru; Chen, Huifen; Bioorganic and Medicinal Chemistry Letters; vol. 25; 21; (2015); p. 4728 – 4732;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

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. 36070-80-1, name is 5-Chloropyrazine-2-carboxylic acid belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below. SDS of cas: 36070-80-1

5-chloropyrazine-2-carboxylic acid (1.00 g, 6.31 mmol),2,2,2-Trifluoroethylamine (687.52 mg, 6.94 mmol),N, N-diisopropylethylamine (3.56 mL, 20.81 mmol),Dissolve O- (7-azabenzotriazol-1-yl) -N, N, N ‘, N’-tetramethyluronium hexafluorophosphate in methylene chloride (30 mL) and stir at room temperature overnight under a nitrogen atmosphere did.Thereafter, saturated aqueous sodium bicarbonate solution was added, extraction was performed with ethyl acetate, and magnesium sulfate was added for dehydration.The magnesium sulfide was removed by suction filtration, the solution was concentrated under reduced pressure, and the composition was purified by silica gel chromatography to give the title compound.(1.10 g, 72.8% yield, white solid)

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

Reference:
Patent; Nippon Kayaku Co.,Ltd.; Hasegawa, Shinji; Ueno, Shotaro; Shinko, Daiki; Kobayashi, Takehiko; Miyake, Takaaki; Asano, Shu; Sumi, Takuto; (101 pag.)JP2019/19124; (2019); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Some common heterocyclic compound, 181284-14-0, name is 3-Chloro-5-methylpyrazine-2-carbonitrile, molecular formula is C6H4ClN3, 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: C6H4ClN3

To a solution of 3-chloro-5-methylpyrazine-2-carbonitrile (19 g, 0.12 mol) and methyl 2-mercaptoacetate (14 g, 0.13 mol) in THF (200 mL) was added NaH (60% dispersion in mineral oil; 7.5 g, 0.19 mol) in small portions at 0 C. The reaction mixture was stirred overnight at RT and then water (200 mL) was carefully added to quench the reaction. The resulting mixture was extracted with ethyl acetate (2 x 300 mL). The combined organic phases were dried over anhydrous sodium sulfate, filtered, and concentrated. The residue was purified via silica gel column chromatography eluting with petroleum ether / EtOAc (90: 10 to 70:30) to afford methyl 7-amino-3-methylthieno[2,3-6]pyrazine-6-carboxylate (20 g, 72%> yield) as a light yellow solid. 1H NMR (400 MHz, DMSO-fifc): delta 8.68 (s, IH), 7.10 (br s, 2H), 3.83 (s, 3H), 2.65 (s, 3H)

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 181284-14-0, its application will become more common.

Reference:
Patent; FORMA THERAPEUTICS, INC.; GUERIN, David Joseph; BAIR, Kenneth W.; CARAVELLA, Justin A.; IOANNIDIS, Stephanos; LANCIA, JR., David R.; LI, Hongbin; MISCHKE, Steven; NG, Pui Yee; RICHARD, David; SCHILLER, Shawn E.R.; SHELEKHIN, Tatiana; WANG, Zhongguo; (113 pag.)WO2017/139779; (2017); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

These common heterocyclic compound, 36070-79-8, name is 6-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. Formula: C5H4ClN3O

General procedure: Comp. 1a and 2a were prepared using microwave reactor. Special thick-walled tubes intended for use in microwave reactor were filled with a mixture of corresponding starting comp. 1 or 2 (150 mg, 0.952 mmol), 25% aqueous ammonia (2 mL, in excess) and MeOH (2 mL). Tubes fitted with stirrer and closed with a special cap were inserted into the reactor. Reaction conditions for microwave-assisted synthesis were: output 200 W, temperature 95 C, reaction time 30 min using PowerMAX mode.

The synthetic route of 6-Chloropyrazine-2-carboxamide has been constantly updated, and we look forward to future research findings.

Reference:
Article; Servusova, Barbora; Paterova, Pavla; Mandikova, Jana; Kubicek, Vladimir; Kucera, Radim; Kunes, Jiri; Dolezal, Martin; Zitko, Jan; Bioorganic and Medicinal Chemistry Letters; vol. 24; 2; (2014); p. 450 – 453;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 63286-28-2, 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. 63286-28-2 name is 2-Chloro-3-hydrazinylpyrazine, 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.

Reference Example 17-2 Preparation of N’-(3-chloropyrazin-2-yl)-1,2,3,4-tetrahydronaphthalene-1-carbohydrazide racemate To a 30 mL cylindrical flask were added 2-chloro-3-hydrazinylpyrazine (470 mg), tetrahydrofuran (5 mL), 1,2,3,4-tetrahydronaphthalene-1-carboxylic acid (573 mg), triethylamine (550 muL), and 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (700 mg) under argon atmosphere, and the resulting mixture was stirred at room temperature for 3 hours. To the reaction mixture were additionally added 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (350 mg) and triethylamine (280 muL), and the resulting mixture was stirred at room temperature for additional 2 hours. The reaction mixture was added to a saturated aqueous solution of sodium hydrogen carbonate, and the resulting mixture was extracted with ethyl acetate. The resulting organic layer was washed with saturated brine, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The resulting residues were subjected to silica gel column chromatography (Rf value=0.23 (solvent: hexane/ethyl acetate=1:1)) (Silica L (40 g), hexane/ethyl acetate=52/48 to 31/69) using YAMAZEN medium pressure preparative column, and the fractions comprising the target compound were concentrated under reduced pressure to give the title compound (308 mg) (yield 31%) as a white solid. MS(CI) m/z: 303/305 [M+H]+

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

Reference:
Patent; MITSUBISHI TANABE PHARMA CORPORATION; UBE INDUSTRIES, LTD.; NAKAJIMA, Tatsuo; HAYASHI, Norimitsu; ISHIZAWA, Kouhei; TSUZAKI, Yasunori; IWAMURA, Ryo; TSUBOIKE, Kazunari; US2019/185479; (2019); 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. 22047-25-2, name is Acetylpyrazine, A new synthetic method of this compound is introduced below., Formula: C6H6N2O

HL was prepared similarly to the published results [37], whereasempolying 2-acetylpyrazine instead of 2-acetylpyridine. In detail, amixture of 2-acetylpyrazine (1.22 g, 10 mmol) and isonicotinoylhydrazide (1.37 g, 10 mmol) in methanol (30 ml) were refluxing for4 h. The pale-yellow solid was precipitated, then filtered andwashed three times by methanol. Yield: 1.54 g (64%). Elementalanalysis for HL (C12H11N5O) (%): Calcd: C: 59.74; H: 4.60; N: 29.03;Found: C: 59.68; H: 4.47; N: 29.24. 1H NMR (400 MHz, CDCl3) d: 9.14(1H)/8.80 (2H)/8.52 (2H)/7.71e7.72 (2H) for AreH, 2.44 (3H, s,eCH3). FT-IR (cm1): n(NH) 3039, n(C]O) 1670 n(C]N) 1555. 13CNMR (100 MHz, CDCl3): d 165.1, 150.3, 149.8, 146.6, 143.2, 145.7,144.4, 140.9, 122.8, 25.9.

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:
Article; Xu, Jun; Zhou, Tao; Xu, Zhou-Qing; Gu, Xin-Nan; Wu, Wei-Na; Chen, Hong; Wang, Yuan; Jia, Lei; Zhu, Tao-Feng; Chen, Ru-Hua; Journal of Molecular Structure; vol. 1128; (2017); p. 448 – 454;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 33332-28-4, These common heterocyclic compound, 33332-28-4, name is 2-Amino-6-chloropyrazine, 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.

The 2-[2-(2,2,2-trifluoroethyl)guanidino]-2-(2-aminoethylthio)pyrazine used as starting material may be obtained as follows: A solution of 2-amino-6-chloropyrazine (1 g.) in warm acetonitrile (15 ml.) was cooled to room temperature. Trifluoroethylisothiocyanate (1.6 g.) was added and the mixture stirred overnight. Further trifluoroethylisothiocyanate (1.6 g.) was added, and the mixture warmed gently on a steam bath for 2 hours, then heated under reflux for 2 hours. The mixture was allowed to cool and evaporated to dryness to yield a brown solid. This was washed with water, 2 N HCl solution, water again, and sucked dry. Recrystallisation from boiling toluene diluted with petroleum ether (b.p. 60°-80°) yielded colourless needles (0.77 g.) of 2-[3-(2,2,2-trifluoroethyl)thioureido]-6-chloropyrazine m.p. 170°-172°.

Statistics shows that 2-Amino-6-chloropyrazine is playing an increasingly important role. we look forward to future research findings about 33332-28-4.

Reference:
Patent; ICI Americas Inc.; Imperial Chemical Industries Ltd.; US4362728; (1982); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 89123-58-0, 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. 89123-58-0, name is 5-Bromopyrazine-2,3-diamine, This compound has unique chemical properties. The synthetic route is as follows.

Step 1 : 6-Bromo-2-(2-cyclopropylpyrimidin-4-yl)-1 /-/-imidazo[4,5-b]pyrazine A mixture of 5-bromopyrazine-2,3-diamine (50 mg, 0.3 mmol) and ethyl 2- cyclopropylpyrimidine-4-carbimidate (Intermediate 19, 50.7 mg, 0.3 mmol), triethylamine (73.8 muIota_, 0.5 mmol), acetic acid (244 muIota_, 4.2 mmol) and ethanol (0.8 mL) was heated to 100C for 30 min. The mixture was concentrated and diluted with water. Then a saturated aqueous solution of sodium bicarbonate was added and the mixture was extracted with ethyl acetate. The organics were washed with brine, dried over sodium sulfate, and concentrated under reduced pressure. The crude material was purified via flash chromatography (0-5% methanol in dichloromethane) to afford 6-bromo-2-(2- cyclopropylpyrimidin-4-yl)-1 H-imidazo[4,5-b]pyrazine (21 mg, 25%).

The chemical industry reduces the impact on the environment during synthesis 5-Bromopyrazine-2,3-diamine. I believe this compound will play a more active role in future production and life.

Reference:
Patent; PFIZER INC.; AHN, Kay; BOEHM, Markus; CABRAL, Shawn; CARPINO, Philip A.; FUTATSUGI, Kentaro; HEPWORTH, David; KUNG, Daniel W.; ORR, Suvi; WANG, Jian; WO2013/150416; (2013); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem