Month: September 2021

Reference of 274-79-3, 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 274-79-3 as follows.

Imidazo[1,2-a]pyrazine (420 mg, 3.53 mmol) was dissolved in acetonitrile (10 mL).N-bromosuccinimide (691 mg, 3.88 mmol) was added thereto, and the mixture was reacted at room temperature overnight.After the reaction is completed, a saturated sodium hydrogencarbonate solution is added thereto.Extract with dichloromethane, dry the organic phase with anhydrous sodium sulfate, filter, and then dry the solvent.The residue was purified by silica gel column chromatography to give a yellow solid,619mg.

According to the analysis of related databases, 274-79-3, the application of this compound in the production field has become more and more popular.

Reference:
Patent; Shanghai Pharmaceutical Group Co., Ltd.; Wan Huixin; Li Chunli; Shi Chen; Liu Haiyan; Li Ping; Shen Jingkang; (50 pag.)CN104341425; (2018); B;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 186534-02-1, A common heterocyclic compound, 186534-02-1, name is 3,5,6-Trimethylpyrazine-2-carbaldehyde, molecular formula is C8H10N2O, 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.

10052] In 10 mL of methanol was dissolved 2,4-dimeth- ylphenylhydrazide hydrochloride (1.72 g, 10 mmol). To the solution, 3,5,6-trimethylpyrazine-2-carbaldehyde (1.50 g, 12 mmol) was added with an ice-bath under the protection of N2. After the mixture was stirred for 10 mm, a lot of brick red precipitate showed and the reaction was then complete. The mixture was filtered through a suction funnel, and the brick red solid was transferred to a vacuum oven to be dried for using directly in the next reaction step of the reaction. The red brick intermediate (3.04 g, 10 mmol) was dissolved in 25 mL of methanol, and 1.68 ml of anhydrous triethylamine and 1.7 ml of trifluoroacetic anhydride were added respectively with an ice-bath under the protection of N2, and the reaction was run for 30 minutes. The reaction was monitored by TLC till completion. The resulting material was extracted with Ethyl acetate, dried over anhydrous Na2504, separated by a silica gel colunm (ethyl acetate:petroleum ether=1 :3) to get T-006 as a light yellow solid (3.25 g, 89.3%). ESI-MS: [M+H] mlz 365.1. ?H-NMR (CDC13, 300 MHz) oe: 2.1 (s, 3H), 2.42 (s, 3H), 2.46 (s, 3H), 2.54 (s, 3H), 2.85 (s, 3H), 7.08 (d, j=7.05 Hz, 1H), 7.24 (d, J=7.21 Hz, 1H), 7.25 (s, 1H), 7.55 (s, 1H); Anal.

The synthetic route of 186534-02-1 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; GUANGZHOU MAGPIE PHARMACEUTICALS CO., LTD.; WANG, Yuqiang; CHEN, Haiyun; ZHANG, Zaijun; ZHANG, Gaoxiao; YU, Pei; SUN, Yewei; SHAN, Luchen; TAO, Liang; US2018/346430; (2018); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 109838-85-9, The chemical industry reduces the impact on the environment during synthesis 109838-85-9, name is (R)-2-Isopropyl-3,6-dimethoxy-2,5-dihydropyrazine, I believe this compound will play a more active role in future production and life.

Preparation 13: [(lS2RV3-arnino-l-(315-Muoro-bemyl)-2-hydroxy-propyl]-carbarnic acid t-butyl ester Step A: (2S,5RV2,5-dihvdro-3,6-dimethoxy-5-isopropyl-2-(3,5-dMuoro)benzylpyrazine(TR.)-2,5-dihydro-3,6-dirnethoxy-2-isopropylpyrazine (9.2 g, 50 mmol) was dissolved in THF (100 mL), to which n-BuLi (4M in THF, 15 mL) was then added at -78 °C, followed by addition of difluorobenzyl chloride (9.72 g, 60 mmol). After the reaction was complete, NH4Cl was added to the reaction mixture which was then extracted with EtOAc. The organic extract was dried over MgSO4 and concentrated under reduced pressure. The residue was purified by column chromatography (EtOAc: n-Hex = 1/1) to afford the title compound (12.4 g, 80percent).

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, (R)-2-Isopropyl-3,6-dimethoxy-2,5-dihydropyrazine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; LG LIFE SCIENCES, LTD.; WO2009/38411; (2009); A2;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 221136-66-9,Some common heterocyclic compound, 221136-66-9, name is Ethyl 2-(3-bromo-6-methyl-2-oxopyrazin-1(2H)-yl)acetate, molecular formula is C9H11BrN2O3, 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 8 r3-(2,2-Difluoro-2-phenyl-ethylamino)-6-methyl-2-oxo-2H-pyrazin-1-vn- acetic acid ethyl ester(3-Bromo-6-methyl-2-oxo-2H-pyrazin-1 -yl)-acetic acid ethyl ester was reacted with 2,2-difluoro-2-phenyl-ethylamine in the presence of a base, at elevated temperature, to yield the title compound as shown in the Scheme above. Table 5 below lists the reagent amounts, base and temperature combinations applied to this reaction, as well as yield.

The synthetic route of 221136-66-9 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; JANSSEN PHARMACEUTICA, N.V.; WO2007/146553; (2007); A2;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 345311-03-7, A common heterocyclic compound, 345311-03-7, name is tert-Butyl 5,6-dihydroimidazo[1,2-a]pyrazine-7(8H)-carboxylate, molecular formula is C11H17N3O2, 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.

1,1-Dimethylethyl 5,6,7,8-tetrahydroimidazo[1,2-a]pyrazin-7-carboxylate (Description 163, 505 mg, 2.26 mmol) in dichloromethane (2.5 mL) was added to stirred, cooled (0 C.) trifluoroacetic acid (5 mL) and the mixture was stirred at 0 C. for 15 minutes, then at room temperature for 45 minutes. The solvent was evaporated under reduced pressure to give the title compound. m/z (ES+) 124 (M+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.

Reference:
Patent; Castro Pineiro, Jose Luis; Dinnell, Kevin; Elliott, Jason Matthew; Hollingworth, Gregory John; Shaw, Duncan Edward; Swain, Christopher John; US2003/236250; (2003); 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. 43029-19-2, name is 3-Aminopyrazin-2(1H)-one, A new synthetic method of this compound is introduced below., Computed Properties of C4H5N3O

General procedure: The pyrazin-2(1H)-one base (11a, 14, 19, 20, 21 or 23) (2 mmol)was added in 1,1,1,3,3,3-hexamethyl-disilazane (HMDS, 10 mL) andheated at 120 for 3 h. Then, the solvent was removed in vacuo asmuch as possible and the obtained residue was dissolved or suspendedin DCM (15 mL), followed by the addition of sugar donor (B or C,2.4 mmol, 1.2 eq.). SnCl4 (2.0 mmol, 1.0 eq.) was added dropwise to thesolution in an ice bath and the reaction mixture was stirred overnight atrt. The solution was diluted with DCM (50 mL), washed with water(20 mL×2), dried over Na2SO4 and concentrated in vacuum. Thecrude residue was purified by silica gel column chromatography to giveintermediates 24a-24e and 27a-27c, which were subsequently treatedwith K2CO3 (2 mmol, 2 eq.) in MeOH (15 mL) to give nucleosides 25 a-25e and 28a-28c.

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:
Article; Guo, Shuang; Xu, Mingshuo; Guo, Qi; Zhu, Fuqiang; Jiang, Xiangrui; Xie, Yuanchao; Shen, Jingshan; Bioorganic and Medicinal Chemistry; vol. 27; 5; (2019); p. 748 – 759;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 186534-02-1,Some common heterocyclic compound, 186534-02-1, name is 3,5,6-Trimethylpyrazine-2-carbaldehyde, molecular formula is C8H10N2O, 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.

General procedure: Take 3,5,6-trimethylpyrazine-2-carbaldehyde (0.15 g, 1 mmol),Dissolved in 10mL of absolute ethanol,10 mL of a solution of substituted acetophenone (1 mmol) in ethanol was added dropwise.Stir for 5 min under ice bath conditions.Add 2.4 mL of 20% NaOH solution dropwise.Ice bath reaction for 0.3h,TLC detects the reaction completely,Add 10% dilute hydrochloric acid to adjust the pH to 5,Add 100mL of water,Filter under reduced pressure,The target compound is obtained by rapid column chromatography.Further, it was subjected to double solvent recrystallization in methanol-water to obtain the target compound Z1-Z16.

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 3,5,6-Trimethylpyrazine-2-carbaldehyde, its application will become more common.

Reference:
Patent; Shandong University; Liu Xinyong; Zou Jinmi; Zhan Peng; (14 pag.)CN108484511; (2018); A;,
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. 4430-75-5, name is Octahydro-2H-pyrido[1,2-a]pyrazine belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below. SDS of cas: 4430-75-5

1-fluoro-2-nitrobenzene (1.2 g, 8.56 mmol),Octahydro-1H-pyrido[1,2-a]pyrazine (1.0 g, 7.13 mmol), N,N-diisopropylethylamine (1.9 mL, 10.7 mmol) was added to N,N-dimethyl In formamide (20 mL),The reaction was heated to 90 C under nitrogen for 4 hours.After completion of the reaction, the mixture was cooled to room temperature, and the reaction mixture was diluted with water (80 mL)The organic phases were combined and washed successively with water (50 mL) and brine (50 mL).Dry over anhydrous sodium sulfate, and distill off the solvent under reduced pressure.The resulting crude product was purified by silica gel column chromatography (petroleum ether: ethyl acetate (V: V) = 5: 1) to give further title compound (yellow oil, 1.74g, 93.4%).

The synthetic route of 4430-75-5 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Guangdong Dongyangguang Pharmaceutical Co., Ltd.; Jin Chuanfei; Du Changfeng; Zhang Yingjun; (29 pag.)CN108409729; (2018); A;,
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. 1458-01-1, name is Methyl 3,5-diamino-6-chloropyrazine-2-carboxylate, A new synthetic method of this compound is introduced below., Formula: C6H7ClN4O2

A mixture of methyl 3,5-diamino-6-chloropyrazine-2-carboxylate (100 g; 494 mmol), methanol (1 l) and NaOH (6 mol/l in water; 240 mL; 1.44 mol) is refluxed for 3 h. The mixture is allowed to cool to r.t. and then neutralized by addition of hydrochloric acid (6 mol/l in water; approx. 240 mL). Water (200 mL) is added. The precipitate formed is filtered off with suction, washed with water and dried at 60° C. C5H5ClN4O2 ESI Mass spectrum: m/z=189 [M+H]+; m/z=187 [M-H]-

The synthetic route of 1458-01-1 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; BOEHRINGER INGELHEIM INTERNATIONAL GMBH; KLEY, Joerg; HECKEL, Armin; US2014/323447; (2014); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 32111-21-0,Some common heterocyclic compound, 32111-21-0, name is 2-Iodopyrazine, molecular formula is C4H3IN2, 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 9 A flask was charged with pinacol borobate (383.0 mg, 1.0 mmol), iodopyrazole (226.6 mg, 1.1 mmol), Pd(OAc)2 (11.2 mg, 0.05 mmol), TFP (46.4 mg, 0.2 mmol), K2CO3 (690.0 mg, 5 mmol), water (3 mL) and DME (2 mL). After 3 vacuum/argon cycles, the resulting mixture was heated to 80 C. 45 min later, HPLC revealed that all boronate disappeared. The area ratio of C-H, coupling product and dimer was about 3.3:85.3:11.4 on HPLC. After the reaction mixture was cooled down to room temperature, EtOAc (5 mL) was added. The aqueous layer was separated and extracted with EtOAc (2*10 mL). The combined organic extracts were washed with brine (10 mL), dried over Na2SO4, and concentrated in vacuo. The crude product was purified via silica gel chromatography to afford the indole (0.27 g, 81%). 1H NMR (300 HMz, CDCl3) delta 8.77 (2H, bs), 8.60 (1H, s), 8.16 (1H, s), 7.82-7.76 (2H, m), 3.96 (3H, s), 3.78 (3H, s), 3.20 (1H, m), 2.08-1.92 (6H, m), 1.72-1.69 (2H, m); 13C NMR (100 HMz, CDCl3) delta 168.0, 147.4, 146.6, 144.4, 143.2, 138.0, 135.3, 129.0, 124.2, 120.5, 120.3, 120.0, 112.4, 52.0, 37.3, 33.6, 31.3, 26.5.

The synthetic route of 32111-21-0 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Boehringer Ingelheim International GmbH; US2006/183752; (2006); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem