Month: June 2021

Related Products of 19745-07-4, A common heterocyclic compound, 19745-07-4, name is 2,5-Dichloropyrazine, molecular formula is C4H2Cl2N2, 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 2 5-Chloro-2-(1′-piperazinyl)-pyrazine hydrochloride The title compound, m.p. 301°-302°, is prepared similarly to Example 1 by substituting 2,5-dichloropyrazine for 2,6-dichloropyrazine.

The synthetic route of 19745-07-4 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Merck & Co., Inc.; US4081542; (1978); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 4774-14-5,Some common heterocyclic compound, 4774-14-5, name is 2,6-Dichloropyrazine, molecular formula is C4H2Cl2N2, 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.

2,2,6,6-tetramethylpiperidine (2.84 g, 20.1 mmol) in THF (250 mL) at -100C was added n-butyllithium (13.8 mL, 22.1 mmol). The solution was stirred for 20 minutes and cooled to -90C. 2,6-Dichloropyrazine (3.0 g, 20.1 mmol) in THF (10 mL) was added to the solution followed by carbon dioxide (89 g, 2014 mmol) as dry ice powder. The mixture was then allowed to warm to room temperature while stirring. The reaction mixture was concentrated under reduced pressure, diluted with water (20OmL) and acidified with 10% aq. HCl solution to pH 2. Extraction with EtOAc (x3) was followed by extraction with saturated aq. NaHCO3 solution. The aquous solution was acidified carefully with 10% aq. HCl solution to pH 2. The solution was extracted with EtOAc(x3) and the resulting solution was washed with water and brine. The organics were dried over anhydrous MgSO4 and concentrated. The resulting solid was trituated with Hex/chloroform (1 :1) and the remaining solid was filtered and washed with hexane to provide the title compound as an off-white solid (1.78 g, 9.22 mmol, 45.8% yield); IH NMR (400 MHz, DMSO-J6) delta ppm 8.90 (s, 1 H).

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 2,6-Dichloropyrazine, its application will become more common.

Reference:
Patent; SIGNAL PHARMACEUTICALS, LLC; WO2009/89042; (2009); 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. SDS of cas: 762240-92-6

Azetidinone lla’ (0.5 g, 2.32 mmol, ee 99.5 %), 3-(trifluoromethyl)-5,6,7,8-tetrahydro-[1 ,2,4]triazolo[4,3-a] pyrazine hydrochloride (Ill’, 1.06 g, 4.65 mmol), Et3N (0.28 g, 4.65 mmol) and 2-ethylhexanoic acid (0.17 g, 1.16 mmol) were suspended in THF (1 0 ml). The resulting suspensionwas stirred at 75C for 72 h. After cooling the mixture to 0C, the excess of the compound Ill’ wasfiltered off and the solvent was removed in vacuo. To the remaining oil was added water (1 0 ml) andthe product was extracted with dichloromethane (3 x10 ml). The organic phases were combined,dried over magnesium sulfate and concentrated in vacuo to give 0.90 g of sitagliptin (IV”) (95%, ee99.5 %) as dark yellow oil.

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

Reference:
Patent; LEK PHARMACEUTICALS D.D.; STARCEVIC, Stefan; MRAK, Peter; KOPITAR, Gregor; WO2013/186326; (2013); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 274-79-3, name is Imidazo[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 274-79-3, Safety of Imidazo[1,2-a]pyrazine

The title compound was prepared from imidazo[1,2-a]pyrazine (500 mg, 4.20 mmol, from Step A) and platinum oxide (250 mg) in methanol (50 mL), using a procedure analogous to that described in Example 1, Step B. Concentration gave the title compound (512 mg) as a viscous oil. 1H NMR (500 MHz, CD3OD) delta 3.37 (t, 1H, J=5.5 Hz), 4.18 (t, 2H, J=5.6 Hz), 4.88 (s, 1H), 7.27 (d, J=1.6 Hz, 1H), 7.33 (d, 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, Imidazo[1,2-a]pyrazine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; Merck Sharp & Dohme Corp.; Edmondson, Scott D.; Fisher, Michael H.; Kim, Dooseop; Maccoss, Malcolm; Parmee, Emma R.; Weber, Ann E.; Xu, Jinyou; US2015/359793; (2015); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 313339-92-3, 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. 313339-92-3 name is 3,5-Dichloropyrazine-2-carbonitrile, 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.

2,3-dichloro-N-[4-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-phenyl]benzenesulfonamide (5.78 g) and 3,5-dichloro – pyrazine-2-carbonitrile (2.35g), 1,1′- bis (diphenylphosphino) ferrocene – dichloropalladium (II) (Pd (dppf) 2Cl2) (791mg) and cesium carbonate (13.2g) was added to a reaction vessel equipped with a magnetic stir bar, then add 100ml of dioxane and 10ml water, stirring the mixture was heated to 100 c for 3h the reaction mixture was cooled to room temperature and treated with saturated aqueous sodium bicarbonate (lml) quenched and extracted with EtOAc (3 X 200ml). the combined aqueous phases were dried over sodium sulfate, filtered and evaporated to give the crude product as a brown oil. using EtOAc and purified by silica gel chromatography using heptane as eluent fast, the solvent was evaporated the solvent under reduced pressure to give a light brown foam 2,3-dichloro-N-[4-(6-chloro-5-cyanopyrazin-2-yl)phenyl]benzenesulfonamide yield:. 4·32g (73%).

At the same time, in my other blogs, there are other synthetic methods of this type of compound, 3,5-Dichloropyrazine-2-carbonitrile, and friends who are interested can also refer to it.

Reference:
Patent; Sanofi; Nazare, M; HALLAND, N; SCHMIDT, F; WEISS, T; Dietz, U; Hofmeister, A; (76 pag.)CN103012407; (2016); B;,
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. 486460-20-2, name is 3-(Trifluoromethyl)-[1,2,4]triazolo[4,3-a]pyrazine, This compound has unique chemical properties. The synthetic route is as follows., Computed Properties of C6H3F3N4

A mixture of 250 mg (1.33 mmol) of 3-(trifluoromethyl)[l,2,4]triazolo[4,3-a]pyrazine(Intermediate 6, Step A), 0.479 mL (4.66 mmol) of 30% hydrogen peroxide aqueous solution, and 2 mLof glacial acetic acid was stirred at 95 C. After 8 h, the solution was cooled and concentrated. Theresidue was partitioned between dichloromethane and saturated sodium bicarbonate aqueous solution.Thin-layer chromatography on silica gel (90:10:1 dichloromethane:methanol:concentrated ammoniumhydroxide solution) revealed that the product was in the aqueous phase. Therefore, the aqueous solutionwas concentrated to dryness, and the residue was purified by preparative HPLC (C18 reverse phasecolumn, 0-50% acetonitrile in water containing 0.05% trifluoroacetic acid) to provide the title compoundas a white solid. LC-MS 205 (M+l).

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 486460-20-2.

Reference:
Patent; MERCK & CO., INC.; WO2006/23750; (2006); A2;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 762240-92-6, A common heterocyclic compound, 762240-92-6, name is 3-(Trifluoromethyl)-5,6,7,8-tetrahydro-[1,2,4]triazolo[4,3-a]pyrazine hydrochloride, molecular formula is C6H8ClF3N4, 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 4-16-Propyl-4-(3-trifluoromethyl-5,6-dihydro-8H-[1,2,4]triazolo[4,3-a]pyrazin-7-yl)thieno[2,3-d]pyrimidine-2-carboxylic acid ethyl ester The compound obtained from Preparation Example 4-1-3 (2.04 g, 7.71 mmol) and the compound obtained from Preparation Example 1-1-2 (1.80 g, 7.87 mmol) were diluted with N,N-dimethylformamide (20 mL), then triethylamine (2.34 g, 23.1 mmol) was added thereto at 0 C. and stirred at room temperature for 16 hours. The resulting mixture was distilled under reduced pressure, then diluted with ethyl acetate and washed with water and salt water. Organic layer was dried with anhydrous magnesium sulfate, distilled under reduced pressure and then purified by column chromatography with the 1:1 mixture of hexane and ethyl acetate to give the title compound (2.56 g, 81%).1H NMR (500 MHz, CDCl3); delta 7.11 (1H, s), 5.37 (2H, s), 4.50 (2H, q), 4.43 (4H, s), 2.93 (2H, t), 1.80 (2H, m), 1.45 (3H, t), 1.02 (3H, t)

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

Reference:
Patent; LG LIFE SCIENCES LTD.; US2011/166121; (2011); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 24241-18-7, 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. 24241-18-7 name is 2-Amino-3,5-dibromopyrazine, 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.

General Procedures; 6,8-Dibromo-imidao[1,2-a]pyrazine; A mixture of 2-Amino-3, 5-dibromopyrazine (72.0 g, 285 mmol) in ethanol (1.1 L) was stirred at room temperature and treated with bromoacetaldehyde diethylacetal (97 mL, 640 mmol), water (72 mL) and concentrated hydrobromic acid (72 mL). The reaction was heated at reflux for five hours, then cooled slowly to room temperature over 16 hours. The resulting white precipitate was then filtered, resuspended in dichloromethane (2 L) and basified with aqueous sodium carbonate solution. After vigorous mixing, the organic phase was separated, dried over MgS04 and concentrated in vacuo, to give a pale yellow solid. Purification of the crude solid was achieved by suspending it in diisopropyl ether (500 mL) and stirring vigorously for one hour. The resulting suspension was filtered to give the title compound (A) as a pale yellow solid (74.5 g, 95 percent).

At the same time, in my other blogs, there are other synthetic methods of this type of compound, 2-Amino-3,5-dibromopyrazine, and friends who are interested can also refer to it.

Reference:
Patent; BIOFOCUS DISCOVERY LIMITED; WO2005/85252; (2005); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 33332-25-1, 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. 33332-25-1, name is Methyl 5-chloropyrazine-2-carboxylate belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below.

Methyl 5-chloropyrazine-2-carboxylate (100 mg, 0.579 mmol, 1 eq), 1-methylpiperazine (65 mul, 0579 mmol, 1 eq) and potassium carbonate (161 mg, 1.159 mmol, 2 eq) were heated in DMSO in a microwave reactor at 120 C. for 5 min. The reaction mixture was poured onto an SCX column (10 g), washed with methanol then eluted with 2M ammonia in methanol. The reaction was repeated as above with methyl 5-chloropyrazine-2-carboxylate (150 mg), 1-methylpiperazine (98 mul) and potassium carbonate (241 mg) in DMSO (3 ml). The product fractions from both reactions were combined and evaporated under vacuum to afford the product as a yellow solid (283 mg, 83%). 1H NMR (399.902 MHz, DMSO) delta 2.23 (s, 3H), 2.42 (t, 4H), 3.73 (t, 4H), 3.82 (s, 3H), 8.38 (d, 1H), 8.66 (d, 1H). MS: m/z 237 (MH+).

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, Methyl 5-chloropyrazine-2-carboxylate, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; ASTRAZENECA AB; US2008/153812; (2008); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 14399-37-2,Some common heterocyclic compound, 14399-37-2, name is 3,6-Dichloropyrazin-2-amine, molecular formula is C4H3Cl2N3, 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 three-necked round-bottle flask was added Y7d (200 mg, 1.22 mmol, 1 equiv), dioxane (4 mL). The solution was vacuated and purged with nitrogen gas three times. Xantphos (l4mg, 0.024 mmol, 0.02 equiv), PdCh(dppf) (8.9 mg, 0.012 mmol, 0.1 equiv), and DIPEA (0.32 g, 2.44 mmol, 2.0 equiv) were added under nitrogen atmosphere. The solution was heated to 85 C for overnight. The reaction was cooled and evaporated. The residue was purified by columnchromatography (eluent/ethyl acetate/heptane = 1/1) to give Zl7d (259 mg, 0.99 mmol, 81%). ‘H NMR (400 MHz, CDCb) d = 7.83 (s, 1H), 4.88 (bs, 2H), 3.73 (s, 3H), 3.47 (t, J= 9.2 Hz, 2H), 2.79 (t, J= 9.2 Hz, 2H).

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 3,6-Dichloropyrazin-2-amine, its application will become more common.

Reference:
Patent; NOVARTIS AG; FEI, Zhongbo; LU, Gang; WAN, Yinbo; WANG, Jianhua; WU, Quanbing; ZHANG, Hao; (116 pag.)WO2020/65453; (2020); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem