Tag: M.W=200-300

762240-92-6, name is 3-(Trifluoromethyl)-5,6,7,8-tetrahydro-[1,2,4]triazolo[4,3-a]pyrazine 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. Computed Properties of C6H8ClF3N4

Example 2: Preparation of benzyl (R)-4-(3-(trifluoromethyl)-5,6-dihydro-[1,2,4]triazolo[4,3-alpha]pyrazin-7(8H)-yl)-1-(2,4,5-trifluorophenyl)-4-oxobutan-2-ylcarbamate (Compound of formula 2 wherein R is Cbz) [39] (R)-3-Cbz-amino-4-(2,4,5-trifluorophenyl)-butanoic acid (3.0g, 8.2mmol) and tetrahydrofuran (THF, 30ml) were charged and dissolved in a dry flask, and N-methylmorpholine (2.7ml, 24.5mmol) was added thereto. Then, the mixture was cooled to a temperature of 0 to 5C, and 2-chloro-4,6-dimethoxy-1,3,5-triazine (1.86g, 10.6mmol) was added thereto. After being stirred at a temperature of 0 to 5C for one hour, 3-(trifluoromethyl)-5,6,7,8-tetrahydro-[1,2,4]triazolo[4,3-alpha]pyrzine hydrochloride (2.05g, 9.0mmol) was added and the reaction mixture was stirred while warming to room temperature (20 to 25C). After the completion of the reaction was confirmed by TLC, the reaction liquid was cooled to 10C, and dichloromethane (30.0ml) and water (30.0ml) were added thereto, followed by separation of layers. The organic layer was washed with saturated sodium bicarbonate (30.0ml) and saline (30.0ml), dried over anhydrous sodium sulfate, concentrated under reduced pressure, and then crystallized from ethyl acetate (12.0ml) and isopropyl alcohol (6.0ml) to afford 3.98g (yield: 90%) of benzyl-(R)-4-(3-(trifluoromethyl)-5,6-dihydro-[1,2,4]-triazolo[4,3-alpha]pyrazin-7(8H)-yl)-1-(2,4,5-trifluorophenyl)-4-oxobutan-2-ylcarbamate.[40] 1H NMR delta7.10-7.34(m, 5H), 7.04(dd, 1H, J=0.012), 6.84(dd, 1H, J=0.013), 5.01(s, 2H), 4.90(NH), 4.20(s, 2H), 4.10(t, 2H), 4.04(t, 2H), 3.97(m, 1H), 2.97(t, 2H), 2.70(t, 2H)

The synthetic route of 762240-92-6 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; ST PHARM CO., LTD.; LIM, Geun Gho; CHANG, Sun Ki; BYEON, Chang Ho; WO2012/99381; (2012); A2;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 63744-22-9, These common heterocyclic compound, 63744-22-9, name is 6,8-Dibromoimidazo[1,2-a]pyrazine, 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.

To a stirred solution of intermediate example 1-1 (8.7 g g, 31.4 mmol) in DMF (210 mL) was added NIS (7.42 g, 33 mmol, 1.05 eq) in one portion at rt. After 18 h stirring at 60 C., the solvent was removed in vaccuo and the residue was taken up in DCM and washed with water and saturated sodium thiosulfate solution. The organic phase was dried over sodium sulphate, filtered and the solvent was evaporated to yield 9.46 g (74.8%) 6,8-Dibromo-3-iodo-imidazo[1,2-a]pyrazine: 1H-NMR (300 MHz, CDCl3): delta=8.22 (1H, s), 7.91 (1H, s) ppm.

The synthetic route of 63744-22-9 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; BAYER INTELLECTUAL PROPERTY GMBH; Koppitz, Marcus; Klar, Ulrich; Jautelat, Rolf; Kosemund, Dirk; Bohlmann, Rolf; Bader, Benjamin; Lienau, Philip; Siemeister, Gerhard; US2013/281460; (2013); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

762240-92-6, name is 3-(Trifluoromethyl)-5,6,7,8-tetrahydro-[1,2,4]triazolo[4,3-a]pyrazine 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. Safety of 3-(Trifluoromethyl)-5,6,7,8-tetrahydro-[1,2,4]triazolo[4,3-a]pyrazine hydrochloride

Example-8: Preparation of 7-[(3R)-3-amino-l-oxo-4-(2,4,5-trifluorophenyl) butyl] – 5,6,7,8-tetrahydro-3-(trifluoromethyl)-l,2,4-triazoIo [4.3-a] pyrazine compound of formula- 1.; To 24 ml of dimethylformamide added 4 gms of (R)-3-(tert-butoxycarbonylamino)-4- (2,4,5-trifluorophenyl)butanoic acid and cooled the reaction mixture to 0-5C. 3.3 gms of NjN’-dicyclohexylcarbodiimide (DCC) was dissolved in 10 ml of dimethylformamide and make upto 20 ml. Added 7 ml of above prepared NjN’-dicyclohexylcarbodiimide (DCC) solution to the above 0-5 C cooled reaction mixture. Added 3.15 gms of 3-(trifluoromethyl)-5,6,7,8-tetra hydro-[l,2,4]triazolo[4,3-a]pyrazine hydrochloride and 3.3 ml of triethylamine to the reaction mixture and stirred for 15 minutes. Added 0.9 gms of dimethylaminopyridine (DMAP) and stirred the reaction mixture for 3 hrs at 0-50C. Added 6.5 ml of N,N’-dicyclohexylcarbodiimide solution and stirred for 3 hrs. Again added 6.5 ml of N,N’-dicyclohexylcarbodiimide solution and stirred for 3 hrs at 0-50C. Raised the temperature to 25C and stirred the reaction mixture for 12 hrs at same temperature. The unwanted precipitated solids were separated by filtration and to the filtrate added water and ethyl acetate. Separated the both aqueous and organic layers. Washed the organic layer with 5% hydrochloric acid solution followed by washed with 5% sodium bicarbonate solution. Distilled off the solvent completely under reduced pressure. Added 30 ml of isopropyl alcohol to the obtained compound and stirred for 45 minutes at 25-300C temperature. Filtered the precipitated solid and dried the material. To the obtained compound added 10 ml of isopropyl alcohol and 3.8 ml of cone, hydrochloric acid. Stirred the reaction mixture for 3 hrs at 500C. Cooled the reaction mixture to 25C and added water. Extracted the compound from reaction mixture with methylene chloride. Distilled off the solvent completely to get the title compound. Yield: 2.5 gms.

The synthetic route of 762240-92-6 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; MSN LABORATORIES LIMITED; SATYANARAYANA REDDY, Manne; ESWARAIAH, Sajja; SATYANARAYANA, Revu; KONDAL REDDY, Bairy; SRINIVAS, Aluru; WO2010/122578; (2010); A2;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 36070-83-4, 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. 36070-83-4, name is Ethyl 5-bromopyrazine-2-carboxylate belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below.

To a mixture of copper powder (286 mg, 4.50 mmol) and DMF (3.5 mL) was added TFA (11 mu, 0.15 mmol), and the resulting mixture was stirred at room temperature for 30 min. To the mixture were added ethyl 5-bromopyrazine-2-carboxylate (VII, 347 mg, 1.50 mmol) and ethyl bromodifluoroacetate (289 mu, 2.25 mmol), and the mixture was stirred at 50 C for 2 h. To the reaction mixture were added a saturated aqueous sodium bicarbonate solution (10 mL) and ethyl acetate (15 mL), and the organic layer was separated. The organic layers was washed twice with an aqueous sodium chloride solution (5%, 20 mL each). After the organic layer was dried over sodium sulfate, concentration at 40 C under reduced pressure and purification of the residue by silica gel chromatography (ethyl acetate and ft-hexane) afforded the title compound (VIII, 30.9 mg, 8% yield and IX, 34.9 mg, 9% yield). [0052] The data of NMR for the title compound (IX) is as follows. [5-(ethoxycarbonyl)pyrazin-2-yl](difluoro)acetic acid (IX) NMR (400 MHz, CDC13) delta: 1.49 (t, J- 6.8 Hz, 3H), 4.55 (q, J = 6.8 Hz, 2H), 9.40 (s, 1H), 9.76 (s, 1H).

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, Ethyl 5-bromopyrazine-2-carboxylate, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; EISAI R&D MANAGEMENT CO., LTD.; YOSHIZAWA, Kazuhiro; OMORI, Masayuki; WATANABE, Yuzo; NAGAI, Mitsuo; TAKAHASHI, Masabumi; FANG, Frank; WO2013/162065; (2013); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 51171-02-9, 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. 51171-02-9 name is Methyl 3-Bromo-2-pyrazinecarboxylate, 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.

A solution of 3-bromopyrazine-2-carboxylic acid methyl ester (0.10 g, 0.45 mmol), 2- tritylsulfanylethylamine (0.29 g, 0.90 mmol) and triethylamine (0.06 mL, 0.44 mmol) in acetonitrile (5 mL) was heated to reflux for 18 h under argon. The mixture was concentrated under reduced pressure and purified by column chromatography (3:1 Hex:EtOAc), yielding 0.058 g (28%) of the desired product.

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

Reference:
Patent; BAYER PHARMACEUTICALS CORPORATION; WO2006/121904; (2006); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 957344-74-0, A common heterocyclic compound, 957344-74-0, name is 5,8-Dibromoimidazo[1,2-a]pyrazine, molecular formula is C6H3Br2N3, 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.

Step 1 4-(5-Bromoiotamiotadazo[l,2-a]pyraziotan-8-ylamiotano) benzoic acid methyl ester[00266] A mixture of 5,8-dibromoimidazo[l,2-a]pyrazme (2g, 7 3mmol), 4-amino benzoic acid methyl ester (0 93g, 6 2mmol), NaO’Bu (0 98g, 10 2mmol), Pd2(dba)3 (133mg, 0 14mmol), Xantphos (168mg, 0 29mmol) and toluene is degassed with nitrogen, then heated at 850C for 18 hours The toluene is removed in vacuo, then MeOH is added to the crude residue The solid is collected by filtration and dried in the vacuum oven The solid is identified as the desired title ester The filtrate is chromatographed with petrol EtOAc (70 30 followed by 50 50) and the fractions containing the desired product, combined, evaporated and triturated with MeOH The resultant solid is collected by filtration and is also identified as the desired ester

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; GALAPAGOS N.V.; WO2007/131991; (2007); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

These common heterocyclic compound, 330786-09-9, name is Methyl 3,5-dichloropyrazine-2-carboxylate, 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 Methyl 3,5-dichloropyrazine-2-carboxylate

Step 1: [0443] Dichloropyrazine S1.1 (synthesized as described in Yamada, K.; Mastuki, K.; Omori, K.; Kikkawa, K. US Patent Application 2004/0142930A1) (0.46 g, 2.7 mmol) was diluted with 10 mL of acetonitrile. To this was then added DIPEA (0.52 mL, 3.0 mmol) and cyclopropylamine (0.19 mL, 2.7 mmol) and the reactions stirred at rt overnight. The following day the reaction was concentrated by rotary evaporation and the resulting syrup diluted with water and stirred until a filterable precipitate formed. The solid was isolated by filtration and washed with water affording the desired product as a bright yellow solid containing regioisomers S1.2 and S1.3.

The synthetic route of Methyl 3,5-dichloropyrazine-2-carboxylate has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Portola Pharmaceuticals, Inc.; Song, Yonghong; Xu, Qing; Jia, Zhaozhong J.; Kane, Brian; Bauer, Shawn M.; Pandey, Anjali; US2013/131040; (2013); 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. 51171-02-9, name is Methyl 3-Bromo-2-pyrazinecarboxylate, A new synthetic method of this compound is introduced below., Safety of Methyl 3-Bromo-2-pyrazinecarboxylate

To a solution of 6.5 g 3-(2-amino-4-chloro-N-methyl-phenylamino)-pyrazine-2-carboxylic acid methyl ester in 100 ml N,N-dimethyl-formamide are added 5.0 g potassium tert. butylate at 0 C. The mixture is stirred at room temperature for 2 hours, poured into ice water and acidified to pH 4 with glacial acetic acid, whereupon the heading compound is precipitated, m.p. 305-307 (recrystallized from methanol). In analogous manner to that described in Example 1, the following compounds of formula I are obtained: The starting materials of formula III for Examples 10-16, 20-23 and 25 are prepared in analogous manner to that described in Example 1, steps (a) to (e). The starting material of formula III for Examples 2 to 5 and 17 may be obtained as follows: 2.2 g of 3-bromo-pyrazine-2-carboxylic acid methyl ester and 2.2 g 1,2-phenylene diamine suspended in 50 ml triethylamine are boiled for 17 hours under reflux. After the mixture has been cooled, water and ethyl acetate are added to precipitate out pyrazino [2,3-b][1,5]benzodiazepin-11(10H)-one, m.p. 298-300.

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; Sandoz Ltd.; US4337198; (1982); A;,
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. 173253-42-4, name is 2-Amino-5-bromo-6-chloropyrazine, This compound has unique chemical properties. The synthetic route is as follows., COA of Formula: C4H3BrClN3

EXAMPLE 27 2-Amino-5-bromo-6-chloropyrazine (0.417 g) was added to a stirred suspension of sodium hydride (oil-free; 0.24 g) in dry dimethoxyethane (20 ml). When evolution of hydrogen ceased, 5-dimethylamino-1-naphthalenesulphonyl chloride (0.594 g) was added. The mixture was stirred for 24 hours and then water (25 ml) and 2M hydrochloric acid (2 ml) were added. The mixture was extracted with ethyl acetate (2*25 ml) and the extracts were dried (MgSO4). Volatile material was removed by evaporation and the residue was purified by elution with ethyl acetate/hexane (1:3 v/v) through a silica gel Mega Bond Elut column to give 5-dimethylamino-N-(5-bromo-6-chloro-2-pyrazinyl)-1-naphthalenesulphonamide (0.46 g), m.p. 180-182 C. (after trituration with ether); mass spectrum (+ve FAB, methanol/NBA): 442 (M+).

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 173253-42-4.

Reference:
Patent; Zeneca Limited; US5861401; (1999); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

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 24241-18-7 as follows. Recommanded Product: 24241-18-7

Reference ASynthesis of 2-bromo-5H-pyrrolo[2,3-b]pyrazineStep 1To a 500 ml three necked round bottom flask, 3,5-dibromopyrazine-2-amine (25.0 g,0.0988 mole) was taken in acetonitrile (250 ml). The reaction mixture was cooled to 0 C and triethylamine (50.0 g, 0.4941 mole), copper (1) iodide (2.26 g, 0.0119 mole), and Pd (PPh3)4 (5.7 g, 0.0049 mole) were added under nitrogen atmosphere. The reaction mixture was stirred for 10 min at 0 C followed by slow addition of trimethylsilylacetylene (10.7g, 0.1089 mole) over 15 min at the same temperature. After completion of the addition, the reaction mixture was warmed up to RT and stirred for 90 min.The completion of the reaction was monitored on TLC using hexanes: ethyl acetate (5:5) as a mobile phase. After completion of the reaction, the reaction mixture was diluted by ethyl acetate and filtered through high flow. Filtrate was collected and washed with water. Layers were separated and aq. layer was re-extracted by ethyl acetate. Attorney Docket No. 11913-1008Combined organic layer was dried over Na2S04, filtered and concentrated to afford crude product which was subjected for the column purification. The crude compound was purified using column purification by eluting the compound with 7-10 % ethyl acetate in hexanes to yield 20.0 g of 5-bromo-3-((trimethylsilyl)ethynyl)pyrazine-2-amine.

According to the analysis of related databases, 24241-18-7, the application of this compound in the production field has become more and more popular.

Reference:
Patent; PRINCIPIA BIOPHARMA INC.; GOLDSTEIN, David Michael; BRAMELD, Kenneth Albert; VERNER, Erik; WO2012/158785; (2012); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem