Pyrazines

Synthetic Route of 186534-02-1, 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. 186534-02-1, name is 3,5,6-Trimethylpyrazine-2-carbaldehyde belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below.

General procedure: New a, b-unsaturated carbonyl-based compounds (5a-g and 6au)were synthesized using direct coupling technique [40] (Scheme 1). The reaction was carried out using base-catalyzed Claisen-Schmidt condensation reaction, by reacting different types of ketoneswith appropriate aromatic aldehyde at molar ratio 2:1 tosynthesize new compounds (5a-g) and at molar ratio 1:1 for (6a-u).For synthesis of 6a-u first 5a-g intermediates were synthesized andin second step appropriate aldehydes were reacted with intermediates.The detailed method of synthesis has already beenreported by us previously [38,40]. Scheme 1 shows the highlights ofsynthesis of compound 3, 4 and a, b-unsaturated carbonyl-basedcompounds along with oxime derivatives. 15 mL ethanol wastaken in a round bottom flask and aromatic aldehyde (20 mmol, 2equivalent) and specific ketone (10 mmol,1 equivalent) were addedand dissolved using a stirrer for 2-3 min at 5 C. Into the abovesolution, 40% NaOH solution in ethanol was added drop wise andthe mixture was stirred for 1-24 h at 27 C. The color change andprecipitate formation in the reaction mixture showed productformation. TLC was used to monitor the reaction and acidified icewas added to quench the reaction once completed. The isolation ofcompounds was done by recrystallization and/or by using columnchromatography.

The synthetic route of 3,5,6-Trimethylpyrazine-2-carbaldehyde has been constantly updated, and we look forward to future research findings.

Synthetic Route of 87486-34-8, These common heterocyclic compound, 87486-34-8, name is 3,5-Dibromo-1-methylpyrazin-2(1H)-one, 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.

Example 197c tert-Butyl 4-(5-(6-Bromo-4-methyl-3-oxo-3,4-dihydropyrazin-2-ylamino)pyridin-2-yl)piperazine-1-carboxylate 197c A mixture of 197b (500 mg, 1.8 mmol), 3,5-dibromo-1-methylpyrazin-2(1H)-one (530 mg, 2.0 mmol), N-ethyl-N-isopropylpropan-2-amine (1.5 mL, 0.90 mmol), and propan-2-ol (20 mL) was stirred at 100°C for 15 h. After the reaction was completed, the solvent was removed under reduced pressure to afford 197c as a brown solid (375 mg, 45percent). MS-ESI: [M+H]+ 465.

Statistics shows that 3,5-Dibromo-1-methylpyrazin-2(1H)-one is playing an increasingly important role. we look forward to future research findings about 87486-34-8.

36070-80-1, name is 5-Chloropyrazine-2-carboxylic acid, 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. Application In Synthesis of 5-Chloropyrazine-2-carboxylic acid

A mixture of 5-chloropyrazine-2-carboxylic acid (1.53 g, 9.66 mmol) in acetonitrile (15 mL, 283 mmol) is treated with DMF (115 muL, 1.49 mmol) and oxalyl chloride (970 muL, 11.1 mmol). The mixture is stirred at ambient temperature under nitrogen for 20 minutes

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

Reference of 768-05-8, The chemical industry reduces the impact on the environment during synthesis 768-05-8, name is Pyrazinoic acid hydrazide, I believe this compound will play a more active role in future production and life.

A solution of Intermediate 6 (100 mg, 0.29 mmol) and pyrazine-2-carbohydrazide (39 mg, 0.29 mmol) in 1-butanol (3 mL) was heated to 130 C. for 16 h. After cooling to rt, the reaction was concentrated to give a brown oil. Purification by chromatography (SiO2; hexanes-100% EtOAc) afforded the desired product as a white solid (94 mg, 75%). MS (ESI): mass calcd. for C19H16ClF3N6O, 436.1; m/z found, 437.1 [M+H]+. 1H NMR (500 MHz, CDCl3) delta 9.62 (d, J=1.5 Hz, 1H), 8.69 (d, J=2.5 Hz, 1H), 8.62 (dd, J=2.5, 1.6 Hz, 1H), 7.77 (d, J=7.7 Hz, 1H), 7.69 (dd, J=7.8, 1.1 Hz, 1H), 7.42 (t, J=7.8 Hz, 1H), 5.56-5.42 (m, 2H), 4.54 (d, J=15.5 Hz, 1H), 4.46 (dd, J=14.1, 4.4 Hz, 1H), 3.77 (ddd, J=9.4, 4.6, 3.5 Hz, 1H), 1.87-1.78 (m, 1H), 1.63-1.53 (m, 1H), 0.97 (t, J=7.4 Hz, 3H).

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, Pyrazinoic acid hydrazide, other downstream synthetic routes, hurry up and to see.

Electric Literature of 951626-95-2, The chemical industry reduces the impact on the environment during synthesis 951626-95-2, name is Ethyl 4-oxo-4,5,6,7-tetrahydropyrazolo[1,5-a]pyrazine-2-carboxylate, I believe this compound will play a more active role in future production and life.

A 60%) dispersion of sodium hydride in mineral oils (0.16 g, 4.0 mmol) was added to a stirred solution of 4,5,6, 7-tetrahydro-4-oxo-pyrazolo[l,5-a]pyrazine-2-carboxylic acid ethyl ester (0.7 g, 3.35 mmol) in DMF (14 mL) at 0 C. The mixture was stirred at room temperature for 1 hour and then benzyl bromide (0.48 mL, 4.0 mmol) was added. The mixture was stirred at room temperature for 16 hours, diluted with H20 and extracted with DCM. The organic layer was separated, washed with brine, dried (NaS04), filtered and the solvents evaporated in vacuo. The crude product was purified by flash columnchromatography (silica; AcOEt in DCM 0/100 to 50/50). The desired fractions were collected and the solvents evaporated in vacuo to yield 4,5,6,7-tetrahydro-4-oxo-5-(phenylmethyl)- pyrazolo[l,5-a]pyrazine-2-carboxylic acid ethyl ester (0.83 g, 83% yield) as a white oil. C16H17N3O3 LCMS: Rt 1.79, m/z 300 [M+H]+ (see LCMS Method 1).

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 4-oxo-4,5,6,7-tetrahydropyrazolo[1,5-a]pyrazine-2-carboxylate, other downstream synthetic routes, hurry up and to see.

Adding a certain compound to certain chemical reactions, such as: 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, 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 762240-92-6, Application In Synthesis of 3-(Trifluoromethyl)-5,6,7,8-tetrahydro-[1,2,4]triazolo[4,3-a]pyrazine hydrochloride

General procedure: A solution of 3-(trifluoromethyl)-5,6,7,8-tetrahydro [1,2,4]triazolo[4,3-a]pyrazine hydrochloride salt (1.0 eq.) in dimethylformamide(DMF, 2-3 mL)was added potassium carbonate (2.5eq.) at and stirred for 15 min at room temperature. To this, N-(benzo[d]thiazol-2-yl)-2-chloroacetamide derivatives (1.0 eq.) in DMF was added to the reaction mixture at room temperature. The resulting reaction mixturewas heated at 70 C for 18 h. The completion of the reaction was monitored on TLC (using 10% MeOH: DCM and ammonia as a modifier as mobile phase) which confirmed that the reaction got completed after 18 h. The reaction mixture was pouredinto ice-cold water and extracted with ethyl acetate (2 x 30 mL).Organic layers were combined and the combined organic layer was dried over sodium sulfate and concentrated under reduced pressure to afford crude desired product and crystallized it from methanol to get N-(benzo[d]thiazol-2-yl)-2-(3-(trifluoromethyl)-5,6-dihydro-[1,2,4]triazolo [4,3-a]pyrazin-7 (8H)-yl)acetamide derivatives(12a-12e) in good practical yield.

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-(Trifluoromethyl)-5,6,7,8-tetrahydro-[1,2,4]triazolo[4,3-a]pyrazine hydrochloride, other downstream synthetic routes, hurry up and to see.

Synthetic Route of 5049-61-6,Some common heterocyclic compound, 5049-61-6, name is Pyrazin-2-amine, molecular formula is C4H5N3, 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.

[0094] Pyrazin-2-amine (VIII) (1.91 g, 20.08 mmol) was dissolved in dimethylsulfoxide (DMSO) (40 mL) and distilled water (1 mL). To the resulting solution was slowly added dropwise N-Bromosuccinimide (NBS) (8.20 g, 46.07 mmol) at 0 C and the solution was stirred at room temperature for 16 hrs. Ice was added to the solution and the solution was stirred to give a yellow solid which was filtered to give the title compound (3.40 mg, 67 %). 1H NMR (400 MHz, CDCl3) delta 8.04 (s, 1H), 5.05 (br, 2H).

The synthetic route of 5049-61-6 has been constantly updated, and we look forward to future research findings.

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. 1458-18-0, name is Methyl 3-amino-5,6-dichloropyrazine-2-carboxylate, A new synthetic method of this compound is introduced below., category: Pyrazines

To a stirring solution of methyl 3-amino-5, 6-dichloropyrazine-2-carboxylate (3.6 g, 16.29 nMol) in MeOH (20 mL) was added NaOH (1.3 g, 32.58 nMol) at 25 . Then the mixture was stirred at this temperature for 16 h. LCMS showed the reaction was complete. Then the mixture was concentrated and residue was poured to water and then extracted with EA (2 x 25 mL) . The organic solution was then concentrated to give the crude product 3-amino-5, 6-dichloropyrazine-2-carboxylic acid (2.6 g, yield: 77.1%) as a yellow solid. LCMS: m/z (ESI) , [M+H] + = 208.1.

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.

Application of 110223-15-9,Some common heterocyclic compound, 110223-15-9, name is 2-Amino-3-benzyloxypyrazine, molecular formula is C11H11N3O, 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.

3-(benzyloxy)pyridin-2-amine (100 mg, 0.50 mmol) and sodium hydride (60% in mineral oil, 22 mg, 0.55 mmol) was dissolved in tetrahydrofuran (0.25M) and then 1-adamantyl isocyanate (106 mg, 0.6 mmol) was added dropwise and heating at reflux for 20 hours. After the reaction was cooled to room temperature, water was added to terminate the reaction, and extracted with ethyl acetate, drying the extracted solution over sodium sulfate, it was filtered and concentrated under reduced pressure. By separation and purification of the residue by column chromatography (ethyl acetate / n-hexane = 1/2) to give the title compound 50 mg at a yield of 26.6%.

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

Adding a certain compound to certain chemical reactions, such as: 69214-33-1, name is 8-Chloroimidazo[1,2-a]pyrazine, 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 69214-33-1, SDS of cas: 69214-33-1

General procedure: The title Compound 30 (12 mg, yield: 19%) was obtained in the same manner as in Example 5 using 4-[2-oxo-3-(piperidin-4-ylmethyl)-3,4-dihydroquinazolin-1(2H)-yl]picolinonitrile dihydrochloride obtained in Step 2 of Example 27 and 8-chloroimidazo[1,2-a]pyrazine. ESI-MS m/z: 465 (M+H)+, 1H-NMR (300 MHz, CDCl3, delta): 8.80-8.78 (m, 1H), 7.84-7.83 (m, 1H), 7.67-7.65 (m, 1H), 7.53 (d, J=1.5 Hz, 1H), 7.48-7.47 (m, 2H), 7.33 (d, J=4.8 Hz, 1H), 7.19-7.07 (m, 3H), 6.40-6.37 (m, 1H), 5.48-5.43 (m, 2H), 4.56 (s, 2H), 3.39 (d, J=6.9 Hz, 2H), 3.10-3.00 (m, 2H), 2.17-2.10 (m, 1H), 1.88-1.85 (m, 2H), 1.52-1.38 (m, 2H) Step 1: 3-{[1-(6,7-Dimethoxyquinazolin-4-yl)piperidin-4-yl]methyl}-3,4-dihydroquinazolin-2(1H)-one (300 mg, 0.69 mmol) obtained by the method described in Chemical & Pharmaceutical Bulletin 1990, 38(6), 1591 was dissolved in DMF (3.0 mL), and sodium hydride (about 60 wt %, 33 mg) and methyl 2-(bromomethyl)-benzoate (190 mg, 0.83 mmol) were sequentially added thereto in an ice bath. After the resulting mixture was stirred at room temperature for 2 hours, a saturated aqueous sodium bicarbonate solution was added to the reaction mixture, and the resulting mixture was extracted with ethyl acetate. The organic layer was washed with saturated brine, and then dried over anhydrous magnesium sulfate and concentrated under reduced pressure. The resulting residue was purified by silica gel column chromatography (a chloroform/methanol mixed solvent), whereby methyl 2-[(3-{[1-(6,7-dimethoxyquinazolin-4-yl)piperidin-4-yl]methyl}-2-oxo-3,4-dihydroquinazolin-1(2H)-yl)methyl]benzoate (355 mg, yield: 88%) was obtained. ESI-MS m/z: 582 (M+H)+, 1H-NMR (400 MHz, CDCl3, delta): 8.66 (s, 1H), 8.04 (d, J=7.8 Hz, 1H), 7.41-7.36 (m, 1H), 7.32-7.27 (m, 2H), 7.15-7.06 (m, 4H), 6.99-6.94 (m, 1H), 6.57 (d, J=8.8 Hz, 1H), 5.52 (s, 2H), 4.57 (s, 2H), 4.22-4.15 (br m, 2H), 4.02 (s, 3H), 3.97 (s, 3H), 3.93 (s, 3H), 3.50 (d, J=7.8 Hz, 2H), 3.12-3.02 (m, 2H), 2.18-2.08 (m, 1H), 1.96-1.87 (br m, 2H), 1.66-1.55 (br m, 2H)

At the same time, in my other blogs, there are other synthetic methods of this type of compound, 8-Chloroimidazo[1,2-a]pyrazine, and friends who are interested can also refer to it.