Tag: M.W=200-300

Application of 51171-02-9, These common heterocyclic compound, 51171-02-9, name is Methyl 3-Bromo-2-pyrazinecarboxylate, 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.

(a) 3-(4-chlorophenylamino)-pyrazine-2-carboxylic acid methyl ester A mixture of 21.7 g 3-bromo-pyrazine-2-carboxylic acid methyl ester and 25.5 g 4-chloroaniline in 150 ml ethyl acetate is boiled 4 days at reflux. The solution is washed with 4 N hydrochloric acid, water and then with 2 N sodium carbonate. The organic phase is dried over sodium sulphate and evaporated to give the heading compound (recrystallized from isopropanol) m.p. 135-136.

Statistics shows that Methyl 3-Bromo-2-pyrazinecarboxylate is playing an increasingly important role. we look forward to future research findings about 51171-02-9.

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. 24241-18-7, name is 2-Amino-3,5-dibromopyrazine, This compound has unique chemical properties. The synthetic route is as follows., name: 2-Amino-3,5-dibromopyrazine

The compound 3,5-dibromo-2-aminopyrazine 1a (20.0 g, 106 mmol) was added to aqueous ammonia (100 mL), and the reaction mixture was reacted at 110 ° C overnight, and the reaction was monitored by LCMS.Pour the reaction system into water (300 mL), extracted with ethyl acetate (500mLx2), the combined organic phases were saturated brine (200mL), dried over anhydrous sodium sulfate and concentrated.The crude product by column (v / v, petroleum ether / ethyl acetate = 30: 1-2: 1) to give the title compound 1b (9.0g, 47.8mmol), 60percent yield

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 24241-18-7.

Reference:
Patent; Shanghai Huahuituo Pharmaceutical Technology Co., Ltd.; Zhejiang Huahai Pharmaceutical Co., Ltd.; Xu Xin; Zhang Tian; Li Yunfei; Wang Guan; Zhu Weibo; Li Qiang; Qu Minkai; Zhang Linli; Song Jinqian; Liu Lei; Chen Haiji; Liu Qiang; Wang Yijin; Ge Jian; (67 pag.)CN109535164; (2019); A;,
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

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

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

These common heterocyclic compound, 486424-37-7, name is 3-Amino-6-bromopyrazine-2-carboxylic acid, 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 3-Amino-6-bromopyrazine-2-carboxylic acid

Example 8 : 3-[5-amino-6-(5-phenyl-l,3,4-oxadiazol-2-yl)pyrazin-2-yl]prop-2-yn-l-ol (Compound 11-90)SCHEME VIIICompound 11-90METHOD H:Step 1 : 3-Amino-6-bromo-iV-(phenylcarbonyl)pyrazine-2-carbohydrazide[00158] TBTU (22.09 g, 68.80 mmol) and triethylamine (4.642 g, 6.394 mL, 45.87 mmol) were added to a suspension of 3-amino-6-bromo-pyrazine-2-carboxylic acid (10 g, 45.87 mmol) and benzohydrazide (7.494 g, 55.04 mmol) in DMF (100.0 mL) and the resulting solution stirred at ambient temperature for 48 hours and then poured into water (400mL) with vigorous stirring. This was allowed to stir for 30 minutes, filtered and washed with water. The moist solid was dissolved in hot EtOAc, dried (MgSC^), filtered and concentrated in vacuo and the resultant solid dried under vacuum to give the desired product (11.34g, 73% Yield). ¾ NMR (400.0 MHz, DMSO) delta 7.51 (2H, m), 7.61 (1H, m), 7.69 (2H, br s), 7.92 (2H, m), 8.44 (1H, s), 10.48 (1H, br s), 10.54 (1H, br s) ppm; MS (ES+) 338.01.

The synthetic route of 3-Amino-6-bromopyrazine-2-carboxylic acid has been constantly updated, and we look forward to future research findings.

Reference:
Patent; VERTEX PHARMACEUTICALS INCORPORATED; CHARRIER, Jean-Damien; DURRANT, Steven, John; KNEGTEL, Ronald, Marcellus, Alphonsus; O’DONNELL, Michael; REAPER, Philip, Michael; WO2011/143419; (2011); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 957344-74-0, These common heterocyclic compound, 957344-74-0, name is 5,8-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.

Typical example of compound of formula (E).General procedure for amine displacement[00251] Amine (1.5eq , 10 8mmol) and (1.5eq, 10.8mmol) are added to a solution of 5,8-dibromo-imidazo[l,2-a]pyrazme (1.99g, 7.2mmol) m ethanol (6mL), and the reaction stirred at 800C for 15 hours. Ethanol is removed in vacuo and the product taken up m DCM and washed with water, dried over MgSO4 and concentrated in vacuo. The resultant oil is passed through a pad of silica using DCM and concentrated in vacuo to yield the desired product; Synthesis of Intermediates Intermediate 1: (5-Bromo-imidazo[l,2-a]pyrazin-8-yl)-(4-chloro-phenyl)-amine.[00254] Following the general procedure for amine displacement 5,8-dibromo-imidazo[l,2- ajpyrazme (1 99g, 7 2mmol) and 4-chloroamlme (1 37g, 10 8mmol) are coupled to give the title compound Purification on silica gel with dichloromethane, methanol (98 2) gives the final product [00255] HPLC (254nm) Rt 3 04mm (100%), m/z (APCI) 323, 325, 327 (M+H)+, 1H NMR(250MHz, CDCl3) delta(ppm) 7 32-7 36 (2H, m), 7 56 (IH, s), 7 64 (IH, m), 7 76-7 80 (3H, m), 7 96 (IH, br s)

Statistics shows that 5,8-Dibromoimidazo[1,2-a]pyrazine is playing an increasingly important role. we look forward to future research findings about 957344-74-0.

Reference:
Patent; GALAPAGOS N.V.; WO2007/131991; (2007); 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. 486424-37-7, name is 3-Amino-6-bromopyrazine-2-carboxylic acid, This compound has unique chemical properties. The synthetic route is as follows., COA of Formula: C5H4BrN3O2

EDAC (2.79 g, 14.5 mmol) was added to a stirring, room temperature solution of IM19B (1.48 g, 7 mmol), 3-amino-6-bromopyrazine-2-carboxylic acid (1.27 g, 5.83 mmol), and hydroxybenzotriazole (0.39 g, 2.9 mmol) in DMSO (9 mL). After stirring for 1 day, 50 mL of water was added to the reaction mixture, to give a gooh. This residue was partitioned between EtOAc (2×100 mL) and additional water (50 mL). The combined organic phases were then extracted with saturated aqueous NaHCO3, dried over Na2SO4, filtered, and concentrated under reduced pressure to give 2.50 g (T.W. 2.40 g) of desired IM19C as a brown oil. TLC: 100% EtOAc Rf=0.55, with slight impurities at Rf=0.75 and Rf=0.9; LC/MS (dissolved in CH3CN/MeOH)>98% (M+H=412, with Br pattern, consistent with desired product, and also a M+23=434, also with Br pattern and also consistent with the desired product). Proceeded and used IM19C for subsequent reaction without further manipulation.

According to the analysis of related databases, 486424-37-7, the application of this compound in the production field has become more and more popular.

Reference:
Patent; Atrin Pharmaceuticals LLC; Breslin, Henry Joseph; Gilad, Oren; (92 pag.)US2016/102104; (2016); 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. 486424-37-7, name is 3-Amino-6-bromopyrazine-2-carboxylic acid belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below. Safety of 3-Amino-6-bromopyrazine-2-carboxylic acid

Step 1 : 3-amino-6-bromo-Lambda/”-(phenylcarbonyl)pyrazine-2-carbohydrazide[00397] TBTU (22.09 g, 68.80 mmol) and Et3N (4.642 g, 6.394 mL, 45.87 mmol) were added to a solution of 3-amino-6-bromo-pyrazine-2-carboxylic acid (10 g, 45.87 mmol) and benzohydrazide (7.494 g, 55.04 mmol) in DMF (100.0 mL) and the resulting solution stirred at ambient temperature overnight. The reaction mixture was poured into water and the resultant precipitate was filtered and dried under vacuum. This was triturated with hot EtOAc and the resulting precipitate filtered and dried to give the desired product (13.11 g, 85% Yield). IH NMR (400.0 MHz, DMSO) d 7.53 (t, 2H), 7.60 (d, IH), 7.69 (br s, 2H), 7.91 (d, 2H), 8.44 (s, IH), 10.48 (s, IH) and 10.55 (s, IH) ppm; MS (ES+) 338.92

The synthetic route of 486424-37-7 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; VERTEX PHARMACEUTICALS INCORPORATED; CHARRIER, Jean-damien; DURRANT, Steven; KAY, David; O’DONNELL, Michael; KNEGTEL, Ronald; MACCORMICK, Somhairle; PINDER, Joanne; VIRANI, Anisa; YOUNG, Stephen; BINCH, Hayley; CLEVELAND, Thomas; FANNING, Lev, T.d.; HURLEY, Dennis; JOSHI, Pramod; SHETH, Urvi; SILINA, Alina; WO2010/54398; (2010); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 136866-30-3,Some common heterocyclic compound, 136866-30-3, name is 3,5-Dichloro-2-iodopyrazine, molecular formula is C4HCl2IN2, 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.

Preparation Example 372 A mixture of 3,5-dichloro-2-iodopyrazine (2 g), cyclopropylboronic acid (750 mg), tetrakistriphenylphosphine palladium (0) (1.68 g), potassium phosphate (3.09 g), toluene (40 mL), and water (4 mL) was stirred at 110 C. overnight. After leaving to be cooled, the insoluble matter was removed by decantation, followed liquid separation by the addition of ethyl acetate and water. The organic phase was washed with saturated brine and dried over anhydrous magnesium sulfate, and then the solvent was evaporated under reduced pressure. The obtained residue was purified by silica gel column chromatography (eluent; hexane:ethyl acetate=98:2) to obtain 3,5-dichloro-2-cyclopropylpyrazine (784 mg) as a colorless oily material.

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 3,5-Dichloro-2-iodopyrazine, its application will become more common.

Reference:
Patent; ASTELLAS PHARMA INC.; Matsuya, Takahiro; Kondoh, Yutaka; Shimada, Itsuro; Kikuchi, Shigetoshi; Iida, Maiko; Onda, Kenichi; Fukudome, Hiroki; Takemoto, Yukihiro; Shindou, Nobuaki; Sakagami, Hideki; Hamaguchi, Hisao; US2014/323463; (2014); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem