Month: July 2021

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. 5521-58-4, name is 5-Methylpyrazin-2-amine, A new synthetic method of this compound is introduced below., name: 5-Methylpyrazin-2-amine

Example 76; (3R)-1-{2-[(5-Methylpyrazin-2-yl)amino]-2-oxoethyl}-3-{[2-piperidin-1-yl-2-(2-thienyl)propanoyl]oxy}-1-azoniabicyclo[2.2.2]octane bromide (Isomer 1); a) 2-Bromo-N-(5-methylpyrazin-2-yl)acetamide; tert-Butyl 5-methylpyrazin-2-ylcarbamate (2.4 g) was heated in hydrochloric acid (50 mL) at 50 C. for 30 min. The brown solution was cooled to RT and made basic by addition of solid sodium carbonate. The products were then extracted with ethyl acetate (2×100 mL) and dried over magnesium sulfate. Concentration of the extracts gave a crude solid. The solid was dissolved in dry DMF (30 mL) and cesium carbonate (11.21 g) added. To the stirred mixture was added bromoacetylbromide and the mixture stirred at RT for 2 h. Water (200 mL) was added, and the mixture extracted with ethyl acetate (2×100 mL). Concentration of the extract to 50 mL and addition of isohexane (100 mL) gave the subtitled compound as a solid (1.640 g).1H NMR (400 MHz, DMSO) delta 11.06 (1H, s), 9.17 (1H, s), 8.31 (1H, d), 4.16 (2H, s), 2.46 (3H, s).

The synthetic route of 5521-58-4 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Ford, Rhonan; Mete, Antonio; Millichip, Ian; Teobald, Barry; US2010/113510; (2010); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Some common heterocyclic compound, 68774-77-6, name is 8-Chloro[1,2,4]triazolo[4,3-a]pyrazine, molecular formula is C5H3ClN4, 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. Application In Synthesis of 8-Chloro[1,2,4]triazolo[4,3-a]pyrazine

A stirred mixture of (-)-R-tert-butyl 4-(aminomethyl)-3,3-difluoropiperidine-1-carboxylate (230mg, 0.92 mmol), 8-chloro-[1,2,4]triazolo[4,3-a]pyrazine (127 mg, 0.83 mmol) and DIPEA (0.30 mL, 1.8 mmol) in n-BuOH (5 mL) was heated to 95C under nitrogen for 13 hr. The reaction mixture was allowed to cool to room temperature and concentrated in vacuo. The residue was purified by column chromatography over silica gel (ethyl acetate/hexane = 1/1) to afford the title compound as a white powder (210 mg, 62%). MS (ESI) calcd for C16H22F2N602: 368.2; found: 369.1 [M+H]. 1H NMR (400 MHz, CDCI3) 6 8.72 (s, 1H), 7.41 (d, J = 4.8 Hz, 1H), 7.35 (d, J = 4.8 Hz, 1H), 6.50-6.45 (m, 1H), 4.47-4.09 (m, 2H), 4.02-3.96 (m, 1H), 3.79-3.72 (m, 1H), 3.09-2.69 (m, 2H), 2.45-2.29 (m, 1H), 1.92-1.87 (m, 1H), 1.68-1.58 (m, 1H), 1.47 (s, 9H).

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 68774-77-6, its application will become more common.

Reference:
Patent; RUGEN HOLDINGS (CAYMAN) LIMITED; SHAPIRO, Gideon; (246 pag.)WO2016/196513; (2016); 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. 762240-92-6, name is 3-(Trifluoromethyl)-5,6,7,8-tetrahydro-[1,2,4]triazolo[4,3-a]pyrazine hydrochloride, This compound has unique chemical properties. The synthetic route is as follows., HPLC of Formula: C6H8ClF3N4

Into a 50 mL round-bottom flask was added 20 mL dichloromethane, followed by the addition of phenyl-butyric acid derivative (3.73 g, 0.01 mol) and triazolopyrazine hydrochloride (228 g, 0.01 mol). The temperature of the reaction mixture was cooled down to 0 C. in an ice-salt bath. 1-Hydroxylbenzotriazole (1.62 g, 0.012 mol) and 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (2.29 g, 0.012 mol) were further added. 3 g Triethylamine was then added dropwise and the mixture was stirred at room temperature for 24 h. The reaction solution was washed with 3×20 mL distilled water. The obtained organic layers were collected and dried over anhydrous magnesium sulfate for 1 h. Then, the desiccant was filtered off and the resulting reactant was concentrated to 4.64 g. The yield was 85%.

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 762240-92-6.

Reference:
Patent; ZHEJIANG HISOAR PHARMACEUTICAL CO., LTD.; Pan, Xianhua; Li, Weijin; Zhang, Qunhui; Ruan, Libo; Yu, Wansheng; Deng, Fei; Ma, Tianhua; Huang, Mingwang; He, Minhuan; US2013/281695; (2013); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 63286-28-2,Some common heterocyclic compound, 63286-28-2, name is 2-Chloro-3-hydrazinylpyrazine, molecular formula is C4H5ClN4, 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.

Step 3: 8-chloro-[1,2,4]triazolo[4,3-a]pyrazine A mixture of 1-(3-chloropyrazin-2-yl)hydrazine (0.90 g, 62 mmol), triethyl orthoformate (2.3 mL), 14 mmol), and dry xylene (15 mL) was refluxed with stirring for 2 h. The mixture was brought to RT, diethyl ether was added and the suspension was filtered. The solid collected was washed with diethyl ether to afford 8-chloro-[1,2,4]triazolo[4,3-a]pyrazine (0.60 g, 62% yield). MS m/z: 155.0 (M+1).

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

Reference:
Patent; Amgen Inc.; US2010/120774; (2010); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

These common heterocyclic compound, 109838-85-9, name is (R)-2-Isopropyl-3,6-dimethoxy-2,5-dihydropyrazine, 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. Safety of (R)-2-Isopropyl-3,6-dimethoxy-2,5-dihydropyrazine

General procedure: Butyl lithium (1.6 N solution in hexane, 1.05 equiv) was added to a solution of (2R)-1 (1 equiv) in anhydrous THF (5 mL) cooled to ?78°C, and the mixture was stirred for 45 min. Imine 2a?f (1 equiv) in THF (4 mL) was added, and the mixture was stirred at ?78°C for 8h. The reaction mixture was allowed to warm to ?10 °C, after which a pH=7 phosphate buffer solution (10 mL) was added, and the mixture was extracted with ethyl acetate (3×10 mL). The organic phase was separated and dried with Na2SO4, and the solvent was evaporated in vacuo. Compounds 3, 4 were purified by means of flash chromatography (SiO2, CH2Cl2/hexane=40/60 for 3a (Rf 0.2) and 4a (Rf 0.4); CH2Cl2/ethyl acetate=95/5 for 3d (Rf 0.4) and 4d (Rf 0.5), 3e (Rf 0.5) and 4e (Rf 0.6); CH2Cl2/ethyl acetate=98/2 for 4f (Rf 0.6)).

The synthetic route of (R)-2-Isopropyl-3,6-dimethoxy-2,5-dihydropyrazine has been constantly updated, and we look forward to future research findings.

Reference:
Article; Cremonesi, Giuseppe; Dalla Croce, Piero; Gallanti, Maddalena; La Rosa, Concetta; Tetrahedron; vol. 70; 11; (2014); p. 2054 – 2058;,
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. Computed Properties of C6H5BrN2O2

(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; US4680297; (1987); A;; ; Patent; Schering Corporation; US4680298; (1987); A;; ; Patent; Schering Corporation; US4740511; (1988); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 24241-18-7, name is 2-Amino-3,5-dibromopyrazine, 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 24241-18-7, COA of Formula: C4H3Br2N3

To a solution of 3,5-dibromopyrazin-2-amine (2.00 g, 7.91 mmol) in THF (24 mL)were added triethylamine (3.3 mL, 24 mmol), cuprous iodide (151 mg, 0.79 mmol) andPd(PPh3hCh (561 mg, 0.79 mmol). The mixture was cooled to -5 oc under nitrogen protection,then trimethylsilylacetylene (1.07 mL, 7.50 mmol) was dropwised slowly into the mixture. Afterthe addition, the mixture was warmed to 0 oc and stirred for 1.5 h. The mixture was concentratedin vacuo to remove the solvent and the residue was purified by silica gel column chromatography(PE/EtOAc (v/v) = 511) to give the title compound as black oil (42 mg, 94 %).MS (ESI, pos. ion) m/z: 272.00 [M+Ht;1H NMR (400 MHz, CDCh) 8 (ppm): 8.04 (s, lH), 5.14 (s, 2H), 0.30 (s, 9H).

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-3,5-dibromopyrazine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; SUNSHINE LAKE PHARMA CO., LTD.; TANG, Changhua; REN, Qingyun; YIN, Junjun; YI, Kai; LEI, Yibo; WANG, Yejun; ZHANG, Yingjun; (303 pag.)WO2018/108125; (2018); A1;,
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. 312736-50-8, name is 3,5-Dichloropyrazine-2-carboxamide belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below. Recommanded Product: 3,5-Dichloropyrazine-2-carboxamide

107261 To a solution of 3,5-dichloropyrazine-2-carboxamide (Example 12, Step 2, 52 g, 0.27 mol) in acetonitrile (1 L) was added POC13 (146 g, 89 mL, 0.95 mol) at room temperature. The mixture was heated to 90-100 C for 4 h. The mixture was cooled to room tempetature and poured slowlyinto a vigorously stirring solution of saturated aq. NaHCO3. Evolution of gas was observed. The mixture was extracted with EtOAc (3 x). The combined organic layers were dried over sodium sulfate then concentrated under reduced pressure to give a residue. The residue was purified by silica gel chromatography (0-30% EtOAc in hexanes) to give the title compound as a pale yellow solid. ?H NIVIR (400 MHz, CDC13): ppm 8.64 (s, 1H): ?3C NMR (101 IVIFIz, CDC13) ppm 150.8,150.43, 143.24, 128.06, 113.06.

The synthetic route of 312736-50-8 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; FLX BIO, INC.; BECK, Hilary, Plake; BIANNIC, Berenger; BUI, Minna Hue, Thanh; HU, Dennis, X.; KETCHAM, John, Michael; POWERS, Jay, Patrick; REILLY, Maureen, Kay; ROBLES-RESENDIZ, Omar; SHUNATONA, Hunter, Paul; WALKER, James, Ross; WUSTROW, David, Juergen; YOUNAI, Ashkaan; ZIBINSKY, Mikhail; (396 pag.)WO2018/22992; (2018); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

58138-79-7, name is 2,6-Diiodopyrazine, 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: C4H2I2N2

1. 2-Iodo-6-allyloxypyrazine This was prepared from 2,6-diiodopyrazine (5.5 g, 16.6 mmol) and allyl alcohol by the procedure described for Example 31 part 1. Chromatography through silica gel using dichloromethane as eluant gave the pure product (2 g), delta (250 MHz, CDCl3) 4.83-4.86 (2H, m, CH2 O); 5.29-5.35 (1H, m, cis-vinyl-H); 5.39-5.48 (1H, m, trans-vinyl-H); 5.98-6.13 (1H, m, vinyl-H); 8.16 (1H, s, pyrazine-H); 8.40 (1H, s, pyrazine-H).

The synthetic route of 58138-79-7 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Merck Sharp & Dohme Limited; US5260293; (1993); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 6966-01-4, A common heterocyclic compound, 6966-01-4, name is Methyl 3-amino-6-bromopyrazine-2-carboxylate, molecular formula is C6H6BrN3O2, 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.

4- (PYRROLIDIN-1-YLSULFONYL) phenylboronic acid (0.33 g, 1.29 mmol), methyl 3-AMINO-6- bromopyrazine-2-carboxylate (0.25 g, 1.08 mmol; described in: H. Ellingson, J. Amer. CLIENT. Soc. 1949, 2798), K3PO3 (3 M, 1.1 ML, 3.2 mmol), and Pd (dppf) C12 (0.044 g, 54 , UMOL) were suspended in ethylene glycol dimethyl ether/water (1.5 : 0.5 mL) and heated in a microwave oven at 160 C for 10 min. The reaction was repeated 3 times. The combined product mixtures were evaporated with silica gel and the crude product was purified by chromatography on silica gel using a heptane to ethyl acetate gradient to give 0.96 g (82% yield) of the title compound: MS (ES) NAL, Z 363 (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:
Patent; ASTRAZENECA AB; WO2004/55006; (2004); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem