Month: March 2021

Electric Literature of 1215852-11-1, A common heterocyclic compound, 1215852-11-1, name is 7-tert-Butyl 3-ethyl 5,6-dihydro-[1,2,4]triazolo[4,3-a]pyrazine-3,7(8H)-dicarboxylate, molecular formula is C13H20N4O4, 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 A: tert-Butyl 3-(2-hydroxypropan-2-yl)-5,6-dihydro-[l,2,4]triazolo[4,3-a]pyrazine-7(8H)-carboxylate. To a solution of 7-tert-butyl 3-ethyl 5,6-dihydro-[l,2,4]triazolo[4,3-a]pyrazine-3,7(8H)-dicarboxylate (0.9 g, 3.04 mmol) in THF (20 mL) at 0C, was added 3 M methylmagnesium iodide in diethyl ether (3.04 mL, 9.11 mmol) dropwise. The reaction was stirred overnight at RT. After 16 hours, the reaction was quenched with saturated aqueous ammonium chloride and extracted with EtOAc. The organic layer was concentrated to provide tert-butyl 3-(2-hydroxypropan-2- yl)-5,6-dihydro-[l,2,4]triazolo[4,3-a]pyrazine-7(8H)-carboxylate as a white powder (0.4 g, 46.6 % yield).

The synthetic route of 1215852-11-1 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; AMGEN INC.; BODE, Christiane, M.; CHENG, Alan, C.; CHOQUETTE, Deborah; LEWIS, Richard, T.; POTASHMAN, Michele, H.; ROMERO, Karina; STELLWAGEN, John, C.; WHITTINGTON, Douglas, A.; WO2012/18668; (2012); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 1245644-42-1, These common heterocyclic compound, 1245644-42-1, name is 6-Bromo-3-iodoimidazo[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 solution of 6-bromo-3-iodoimidazo[l ,2-a]pyrazine (3 g, 9.26 mmol) in DMF (50 mL), were added 4-cyanophenylboronic acid 3 (1.632 g, 11.1 mmol), K3P04 (4.91 g, 23.15 mmol), Pd(PPh3)4 (0.534 mg, 0.46 mmol) and water (5 mL). The reaction mixture was heated at 90 C for 1 h and water was added to the mixture to induce precipitation. The precipitate was isolated by filtration and was purified by column chromatography (silica gel, eluent petroleum ether/EtOAc 1 :1) to afford of 4-(6-bromoimidazo[l,2-a]pyrazin-3-yl)benzonitrile (2.5 g, 90%) as an off-white solid. 1H NMR (400 MHz, DMSO-< delta 9.88 (s, 1H), 8.90 (s, 1H), 8.27 (s, 1H), 8.05-7.99 (m, 4H); MS (ESI) m/z 301.1 [C13H7BrN4+2 ]+. The synthetic route of 1245644-42-1 has been constantly updated, and we look forward to future research findings. Reference:
Patent; AGENCY FOR SCIENCE, TECHNOLOGY AND RESEARCH; NACRO, Kassoum; DURAISWAMY, Athisayamani, Jeyaraj; CHENNAMANENI, Lohitha, Rao; WO2013/147711; (2013); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 17231-51-5, 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 17231-51-5 as follows.

Step 1 [0188] A 50 mL RBF equipped with magnetic stir bar was charged with 1.0 g (1.0 eq.) Bromo amine, 1 .6 g (2.2 eq.) methyl Iodide, and 3.7 g (2.2 eq.) CsC03 in 25 ml DMF. The reaction was stirred at RT. The reaction mixture got dark and was let to stir overnight. LC/MS looks like previous runs. The reaction was partionned between EA and aq. Citric. The organics were washed with satd. bicarb, brine, dried and concentrated in vacuo to crude. Purification was done by Flash Chromatography (20 – 50 % EA-H). The fractions containing visible yellow product (even if some had some long wave impurities) were combined and concentrated then vacuum dried to afford 940 mgs of crystalline solid.

According to the analysis of related databases, 17231-51-5, the application of this compound in the production field has become more and more popular.

Reference:
Patent; MALLINCKRODT LLC; FRESKOS, John, N.; WO2013/39851; (2013); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 173253-42-4, These common heterocyclic compound, 173253-42-4, name is 2-Amino-5-bromo-6-chloropyrazine, 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.

7. 2,6-Diamino-3-bromopyrazine A suspension of 2-chloro-3-bromo-6-aminopyrazine (15 g, 0.072 mole) in absolute ethanol (150 ml) and 0.880 ammonia (375 ml) was stirred and heated in an autoclave at 160 C. and 20 atm. for 16 hrs. The cooled mixture was evaporated in vacuo and extracted with hot methanol (3*100 ml). The combined methanol extracts were evaporated in vacuo. The residue was dissolved in hot chloroform, dried over anhydrous magnesium sulphate, filtered and the filtrate evaporated in vacuo. The residue was triturated with 40-60 C. petroleum ether, filtered, and dried in vacuo. Yield 5.51 g (40%), M.p. 176-178 C.

Statistics shows that 2-Amino-5-bromo-6-chloropyrazine is playing an increasingly important role. we look forward to future research findings about 173253-42-4.

Reference:
Patent; Glaxo Wellcome, Inc.; US6255307; (2001); B1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 36070-79-8, name is 6-Chloropyrazine-2-carboxamide, 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 36070-79-8, Computed Properties of C5H4ClN3O

General procedure: 150 mg (0.952 mmol) of 5-Cl-PZA (1) or 6-Cl-PZA (2) was dissolved in ethanol together with triethylamine (1 eq., 96 mg, 0.952 mmol). Three equivalents of corresponding alkylamine were added to the reaction mixture and refluxed in ethanol generally for 6 hours. The completion of the reaction was checked by TLC chromatography (eluent: hexane/ethyl acetate, 1:2). The crude product was absorbed on silica by solvent evaporation and purified by flash chromatography (hexane/ethyl acetate gradient elution).

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, 6-Chloropyrazine-2-carboxamide, other downstream synthetic routes, hurry up and to see.

Reference:
Article; Servusova, Barbora; Paterova, Pavla; Mandikova, Jana; Kubicek, Vladimir; Kucera, Radim; Kunes, Jiri; Dolezal, Martin; Zitko, Jan; Bioorganic and Medicinal Chemistry Letters; vol. 24; 2; (2014); p. 450 – 453;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

5049-61-6, name is Pyrazin-2-amine, 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 Pyrazin-2-amine

To a solution of aminopyrazine (4l) (10.0 g, 105 mmol) in DMSO (200 mL) and water (5 mL) was added N-bromosuccinimide (39.3 g, 221 mmol) at room temperature, and the mixture was stirred for 23 hours. To the mixture was added water and the product was extracted with diethyl ether (300 mL*4). The combined organic extract was washed successively with water (400 mL*2) and brine (500 mL*2), followed by drying over anhydrous sodium sulfate. After filtration and concentration under reduced pressure, the residue was purified by column chromatography (silica gel 280 g, n-hexane/dichloromethane/ethyl acetate=5/4/1). The resulting solid was further purified by recrystallization (n-hexane/ethyl acetate) to give Compound 42 (17.3 g, 68.3 mmol, 64.9%) as a colorless solid. Rf=0.48 (n-hexane/dichloromethane/ethyl acetate=5/4/1); 1H NMR (400 MHz, CDCl3) delta 5.05 (s, 2H), 8.05 (s, 1H).

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

Reference:
Patent; Inouye, Satoshi; Sahara, Yuiko; Hosoya, Takamitsu; US2014/316137; (2014); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 110223-15-9, name is 2-Amino-3-benzyloxypyrazine, 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 110223-15-9, Safety of 2-Amino-3-benzyloxypyrazine

General procedure: For aromatic urea derivatives; the appropriate aromatic isocyanate(3.0 mmol) was added to a solution of the appropriate 2-amino-3-benzyloxy pyrazine derivative (2.5 mmol) in THF(10 mL). The reaction was refluxed for 3e6 h. After cooling, thereaction mixture was evaporated and the residue was purified byprecipitation in cold methanol and filtered to give the targetcompound(s). For aliphatic urea derivatives; the appropriatealiphatic isocyanate derivative (1.02 mmol) was added to a solutionof the appropriate 2-amino-3-benzyloxy pyrazine derivative(0.85 mmol) in dry THF (5 mL) in the presence of NaH (60% inmineral oil, 68 mg, 1.71 mmol). The reaction was refluxed for 5 h.After cooling, the reaction mixture was evaporated and the residuewas purified by flash column chromatography (SiO2, EA/n-Hex 1/4).

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-benzyloxypyrazine, other downstream synthetic routes, hurry up and to see.

Reference:
Article; Elkamhawy, Ahmed; Park, Jung-eun; Hassan, Ahmed H.E.; Pae, Ae Nim; Lee, Jiyoun; Paik, Sora; Park, Beoung-Geon; Roh, Eun Joo; European Journal of Medicinal Chemistry; vol. 157; (2018); p. 268 – 278;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 27398-39-6, These common heterocyclic compound, 27398-39-6, name is 3-Chloropyrazine-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.

1.59 g (10 mmol) of 3-chloropyrazine-2-carboxylic acid was dissolved in 20 mL of dichloromethane solvent, 2.54 g (20 mmol) of oxalyl chloride, 2 drops of DMF,After stirring at reflux for 5 h, the solvent and excess oxalyl chloride were evaporated under reduced pressure.Obtained a purplish red oil; it was dissolved in 20 mL of dichloromethane.Add 0.92g (5mmol)Ethyl 5-(methylaminomethyl)-1H-imidazole-4-carboxylate and1.52 g (15 mmol) of triethylamine,After stirring at room temperature until the reaction was completed, it was poured into 50 mL of saturated sodium bicarbonate solution, and extracted with dichloromethane (20 mL ¡Á 4).After filtration, the solvent was evaporated under reduced pressure to give ethyl 5-((3-chloro-N-methylpyrazine-2-carboxamido)methyl)-1H-imidazole-4-carboxylate.Ethyl 5-((3-chloro-N-methylpyrazine-2-carboxamido)methyl)-1H-imidazole-4-carboxylate was dissolved in 20 mL of acetonitrile.Add 3.26 g (10 mmol) of cesium carbonate,The mixture was stirred under reflux until the reaction was completed, and the solvent was evaporated under reduced pressure.It was dissolved in 20 mL of dichloromethane.Wash with distilled water (30 mL ¡Á 2), dry over anhydrous sodium sulfate,After filtration, the solvent was evaporated under reduced pressure.Column chromatography (EtOAc, 1percent Et3N),A white solid was obtained in a two step yield of 55percent.

The synthetic route of 27398-39-6 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; The Chinese People’s Liberation Army Military Academy Of Medical Sciences Poison Pharmaceutical Institute; Beijing Normal University; Yu Gang; Zhang Zhanbin; Cao Yanqing; Su Ruibin; Zheng Zhibing; Zhou Xinbo; Li Yi; Xiao Guiying; (16 pag.)CN109206428; (2019); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

These common heterocyclic compound, 33332-25-1, name is Methyl 5-chloropyrazine-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. Application In Synthesis of Methyl 5-chloropyrazine-2-carboxylate

To a solution of methyl-5-chloropyrazine-2-carboxylate (120 mg, 0.70 mmol) in a mixture of acetonitrile (2 mL) and DMF (1 mL) was added lithium chloride (295 mg, 6.95 mmol). The suspension was heated to 160C for 5 mins in a Smith creator microwave after which time the reaction was diluted with water (10 mL). Saturated sodium bicarbonate solution (20 mL) was added and the aqueous layered extracted twice with ethyl acetate (30 mL). The combined organics were discarded and the aqueous layer adjusted to pH 4 with IN hydrochloric acid. The aqueous phase was extracted twice with ethyl acetate (20 mL) and the combined organics washed with water (2 x 20 mL), brine (10 mL) and dried (MgSO4). The volatiles were removed to give the title compound as a colourless solid (68 mg). 1H NMR delta (CDCl3): 7.20 (IH, br s), 8.72 (IH, s), 9.21 – 9.21 (IH, m); m/z 157 (M-H)+.

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

Reference:
Patent; ASTRAZENECA AB; ASTRAZENECA UK LIMITED; WO2007/7041; (2007); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 74290-69-0, name is 5-Bromo-6-methylpyrazin-2-amine, 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 74290-69-0, Computed Properties of C5H6BrN3

Compound 9 was prepared by reacting compound 7 (3.18 g;11 mmol) with compound 8 (1.88 g; 10 mmol) in the presence of Pd(PPh3)4 (250 mg) and Na2CO3 (6.36 g; 60 mmol) in THF (120 mL containing10% water) for 12 h at 343 K. Compound 9 was purified bycolumn chromatography on silica gel using petroleum ether/ethyl acetate(15:1, v/v) as eluent. A yellow solid was obtained with 90% yield.M.p.: 454-455 K. 1H NMR (400 MHz, DMSO-d6 TMS), delta (ppm): 7.78 (s,1H), 7.43 (d, J 8.4 Hz, 2H), 7.30 (t, J 7.6 Hz, 4H), 7.04 (d,J 8.0 Hz, 4H), 7.03 (d, J 5.2 Hz, 2H), 6.99 (d, J 8.4 Hz, 2H), 6.35 (s, 2H), 2.36 (s, 3H). 13C NMR (101 MHz, DMSO-d6, TMS) delta (ppm):153.6, 147.3, 147.1, 146.1, 139.4, 133.6, 129.7, 129.5, 128.8, 124.0,123.0, 122.5, 22.6. ESI-MS (ESI, m/z): [M] calcd of C23H20N4, 352.1;found, 353.2, [M H].

If you are interested in these compounds, you can also browse my other articles.Thank you for taking the time to read this article. I hope you enjoyed it.

Reference:
Article; Shi, Fu; Cui, Shiqiang; Liu, Hongling; Pu, Shouzhi; Dyes and Pigments; vol. 173; (2020);,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem