Heterocyclic Building Blocks-quinoxaline

91-19-0,With the rapid development and complex challenges of chemical substances, new drug synthesis pathways are usually the most effective.91-19-0,Quinoxaline,as a common compound, the synthetic route is as follows.

Bromine (3.84g, 24mmol) was added dropwise to a magnetically stirred refluxing mixture of quinoxaline (1) (390mg, 3.0mmol) and barium carbonate (1.20g, 6.1mmol) in acetonitrile (20mL). The resulting reaction mixture was heated at reflux temperature for 25h and allowed to warm to room temperature. The solvent was evaporated and the mixture was diluted with a saturated solution of sodium carbonate (10mL). The mixture was extracted with ethyl acetate (3¡Á25mL) and combined organic layers were washed with water, dried over Na2SO4 and concentrated. The residue was purified via column chromatography on silica gel (100g) by eluting with 15% EtOAc/n-hexane. The first fraction was 6-bromoquinoxaline (10) (195mg, 31%) data as before. The second fraction was 5,8-dibromoquinoxaline (12) (45mg, 5%) data as before. The third fraction was 6,7-dibromoquinoxaline (13) (50mg, 6%) data as before. The fourth fraction was 5,7-dibromoquinoxaline (11) (120mg, 14%) data as before. The fifth fraction was 5,6-dibromoquinoxaline (14) (240mg, 28%) data as before.

The synthetic route of 91-19-0 has been constantly updated, and we look forward to future research findings.

Reference£º
Article; Ucar, Sefa; E?siz, Selcuk; Da?tan, Arif; Tetrahedron; vol. 73; 12; (2017); p. 1618 – 1632;,
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3476-89-9, 1,2,3,4-Tetrahydroquinoxaline is a quinoxaline compound, ?involved in a variety of chemical synthesis. Rlated chemical reaction is continuously updated

A solution of 5-(3,4,5-trimethoxyphenyl)penta-(2E,4E)-dienoyl chloride in methylene chloride (3 ml) was added dropwise to a solution of 45 mg (0.34 mmol) of 1,2,3,4-tetrahydroquinoxaline(1) in pyridine (0.5 ml) over about 5 minutes with stirring in an ice bath.. After completion of the addition, the mixture was stirred for 1 hour and water was added to conduct extraction with chloroform.. An organic layer was dried over anhydrous sodium sulfate and then concentrated under reduced pressure.. The resultant crude oil (254 mg) was purified by column chromatography on alumina and column chromatography on silica gel to obtain 91 mg (yield: 43%) of crude crystals of the title compound.. The crude crystals were recrystallized from chloroform-ether to obtain pale yellow fien needles. Melting point: 183-185 C. 1H-NMR (DMSO-d6, 120 C.) delta: 3.71(s,6H), 3.80(s,12H), 3.97(s,4H), 6.52(d,J=14.9 Hz,2H), 6.80(s,4H), 6.85-7.00(m,4H), 7.21-7.28(m,2H), 7.36(ddd,J=14.9,9.0,1.1 Hz,2H), 7.38-7.45(m,2H)., 3476-89-9

As the paragraph descriping shows that 3476-89-9 is playing an increasingly important role.

Reference£º
Patent; Kowa Co., Ltd.; US6340682; (2002); B1;,
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With the rapid development and complex challenges of chemical substances, new drug synthesis pathways are usually the most effective.23088-23-5,Methyl 6-Quinoxalinecarboxylate,as a common compound, the synthetic route is as follows.

To a solution of methyl quinoxaline-6-carboxylate (500 mg, 2.66 mmol) in 10 mL of THF was added sodium hydroxide (5N, 2.5 mL, 12.5 mmol) followed by methanol (2.5 mL). The reaction was stirred at room temperature overnight and then concentrated in vacuo to remove THF/MeOH. The resulting aqueous mixture was acidified with IN HCl until the pH was slightly acidic (pH = 5). The resulting solution was extracted with EtOAc (3x), and the combined organic layers were then washed with brine, dried over anhydrous MgSO4, filtered and concentrated in vacuo. The resulting white solid was used without further purification. LC-MS: 3.50 min. (M+H) = 175.16, 23088-23-5

The synthetic route of 23088-23-5 has been constantly updated, and we look forward to future research findings.

Reference£º
Patent; MERCK & CO., INC.; WO2006/14618; (2006); A2;,
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With the rapid development and complex challenges of chemical substances, new drug synthesis pathways are usually the most effective.1204-75-7,3-Oxo-3,4-dihydroquinoxaline-2-carboxylic acid,as a common compound, the synthetic route is as follows.

The resulting compound (190 mg, 0.600 mmol) was condensed with 3-hydroxyquinoxaline-2-carboxylic acid (110 mg, 0.600 mmol) to afford N-[(1S)-1-{[4-(cyclohexyloxy)piperidin-1-yl]carbonyl}-2-methylpropyl]-3-hydroxyquinoxaline-2-carboxamide (219 mg, yield 81%) as a pale yellow solid. 1H-NMR (DMSO-d6, 400 MHz) delta: 12.81 (1H, brs), 9.45 (1H, t, J=8.3 Hz), 7.86 (1H, d, J=8.3 Hz), 7.63 (1H, t, J=7.5 Hz), 7.39-7.36 (1H, m), 4.86 (1H, dd, J=16.1 Hz, 9.3 Hz), 3.95-3.88 (2H, m), 3.70-3.63 (1H, m), 3.39-3.27 (3H, m), 3.19-3.06 (1H, m), 2.51-2.49 (4H, m), 1.92-1.11 (11H, m), 0.95-0.92 (6H, m). IR (ATR) cm-1: 2930, 1690, 1640, 1530, 1475, 1450, 1090. MS (ESI, m/z): 455 (M+H)+. Anal. Calcd for C25H34N4O4: C, 66.06; H, 7.54; N, 12.33. Found: C, 65.77; H, 7.47; N, 12.33., 1204-75-7

As the paragraph descriping shows that 1204-75-7 is playing an increasingly important role.

Reference£º
Patent; Daiichi Sankyo Company, Limited; EP2258697; (2010); A1;,
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1204-75-7, 3-Oxo-3,4-dihydroquinoxaline-2-carboxylic acid is a quinoxaline compound, ?involved in a variety of chemical synthesis. Rlated chemical reaction is continuously updated,1204-75-7

Step S (Compound 19) [00157] 3-Hydroxy-2-quinoxaline carboxylic acid (15.0 g/78.9 mmol) was dissolved in concentrated sulfuric acid (225 ml). The reaction mixture was cooled in an ice-water bath and added slowly was Potassium nitrate (24.0 g/237.4 mmol). After completion of addition, the cooling bath was removed and the reaction mixture was allowed to reach room temperature where it was stirred overnight. The reaction mixture was poured onto ice (900 g) and the resulting precipitate was filtered. The solid was dissolved in boiling water (2.4 L) and filtered hot. Upon cooling to room temperature, the precipitated product was collected by filtration and washed with Et20. Yield: 11.40 g (62%, approximately) 1H NMR (500 MHz, DMSO-d6) 8 8.61 (s, 1H), 8. 46 (d, 1H), 7.50 (s, 1H).

As the paragraph descriping shows that 1204-75-7 is playing an increasingly important role.

Reference£º
Patent; VERTEX PHARMACEUTICALS INCORPORATED; WO2005/56547; (2005); A2;,
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With the rapid development and complex challenges of chemical substances, new drug synthesis pathways are usually the most effective.1204-75-7,3-Oxo-3,4-dihydroquinoxaline-2-carboxylic acid,as a common compound, the synthetic route is as follows.,1204-75-7

To a stirred solution of Cu(ClO4)2*6H2O (18.75 mg, 0.05mmol) in H2O (2 mL) was added 1 equiv. of pyrazine (4 mg,0.05 mmol) in CH3OH (5 mL). This was stirred for 5 min,and then a 5 mL CH3OH solution of 3-hydroxy-2-quinoxalinecarboxylic acid (9.5 mg, 0.05 mmol) wasadded to the reaction mixture and then filtered to givea green solution. Slow evaporation of the solvent atroom temperature gave rise to green block single crystals suitable for X-ray single-crystal analysis after ca 5 days. Yield: 40% (based on Cu). Anal. calcd forC22H20CuN6O10: C, 44.64; H, 3.41; N, 14.20%. Found: C,44.58; H, 3.49; N, 14.27%; IR (KBr)/cm-1: 3464(m),1683(s), 1609(m), 1374(m), 1326(m), 1221(w), 986(w),882(w), 806(w), 776(m), 676(m), 446(w).

As the paragraph descriping shows that 1204-75-7 is playing an increasingly important role.

Reference£º
Article; Liu, Qi; Wu, Huai Guang; Comptes Rendus Chimie; vol. 16; 5; (2013); p. 451 – 461;,
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With the rapid development and complex challenges of chemical substances, new drug synthesis pathways are usually the most effective.1593-08-4,2-Formylquinoxaline,as a common compound, the synthetic route is as follows.,1593-08-4

The piperazine template (0.075 g, 0.213 mmol) of Example 24 was dissolved in 1,2-dichloroethane (3 mL) and treated with quinoxaline-2-carbaldehyde (0.044 g, 0.277 mmol) and glacial acetic acid (2 drops). Sodium triacetoxyborohydride (0.090 g, 0.426 mmol) was added, and the mixture was stirred at room temperature until the reaction was complete by LCMS analysis. The solvent was removed under reduced pressure, and the resulting residue was purified by RP-HPLC to yield the free base (0.0578 g, 55% yield). MS (ESI) m/z 494.

As the paragraph descriping shows that 1593-08-4 is playing an increasingly important role.

Reference£º
Patent; Wyeth; US2006/264631; (2006); A1;,
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1593-08-4, 2-Formylquinoxaline is a quinoxaline compound, ?involved in a variety of chemical synthesis. Rlated chemical reaction is continuously updated,1593-08-4

General procedure: To a stirred solution of amine (6) (100 mg,0.407 mmol) in ethanol was added amines (7.1-7.9) (0.407mol) followed by anhydrous sodium sulphate (0.407 mmol) and stirred at 50 C for 1 h. The hot homogenous solution was filtered and cooled to 5 C to isolate the corresponding imines (8.1-8.9) in quantitative yields.

As the paragraph descriping shows that 1593-08-4 is playing an increasingly important role.

Reference£º
Article; Sreedhar, Pandiri; Srinivas, Gudipati; Raju, Rallabandi Madhusudan; Asian Journal of Chemistry; vol. 28; 7; (2016); p. 1603 – 1606;,
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2958-87-4, 2,3,6-Trichloroquinoxaline is a quinoxaline compound, ?involved in a variety of chemical synthesis. Rlated chemical reaction is continuously updated,2958-87-4

To a solution of 2,3,6-trichloro-quinoxaline (100 mg, 0.43 mmol) in DMF (3 mL) was added N-methylpiperazine (0.47 mL, 0.43 mmol). The reaction mixture was stirred for 12 h, and then the solvent was removed in vacuo. The residue was purified by silica gel chromatography to give 47 mg of 2,6-dichloro-3-(4-methyl-piperazin-1-yl)-quinoxaline and 28 mg of 3,6-dichloro-2-(4-methyl-piperazin-1-yl)-quinoxaline. 2,6-Dichloro-3-(4-methyl-piperazin-1-yl)-quinoxaline: 1H NMR (400 MHz, CDCl3): 7.80 (d, J=2.3 Hz, 1H), 7.77 (d, J=8.8 Hz, 1H), 7.46-7.43 (dd, J=8.8, 2.3 Hz, 2H), 3.63-3.62 (m, 4H), 2.64-2.61 (m, 4H), 2.38 (s, 3H). 3,6-Dichloro-2-(4-methyl-piperazin-1-yl)-quinoxaline: 1H NMR (400 MHz, CDCl3): 7.85 (d, J=2.3 Hz, 1H), 7.75 (d, J=8.8 Hz, 1H), 7.59-7.56 (dd, J=8.8, 2.3 Hz, 2H), 3.63-3.61 (m, 4H), 2.64-2.62 (m, 4H), 2.39 (s, 3H).

As the paragraph descriping shows that 2958-87-4 is playing an increasingly important role.

Reference£º
Patent; Edwards, James P.; Venable, Jennifer D.; US2005/70527; (2005); A1;,
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49679-45-0, Ethyl 3-chloroquinoxaline-2-carboxylate is a quinoxaline compound, ?involved in a variety of chemical synthesis. Rlated chemical reaction is continuously updated,49679-45-0

STEP A: 1-carbethoxycarbonylmethyl-2-amino-3-carbamoyl-quinoxalinium bromide A solution of 1 g of 2-amino-3-carbamoyl-quinoxaline prepared from 2-chloro-3-carbethoxy-quinoxaline by the method of Gowenlock et al [J. Chem. Soc., 1945, p. 622-5] in 50 ml of dimethoxy ethane and ethyl bromopyruvate was stirred for 2 days and was filtered to obtain 1.44 g of 1-carbethoxycarbonylmethyl-2-amino-3-carbamoyl-quinoxalinium bromide as a yellow crystalline solid.

As the paragraph descriping shows that 49679-45-0 is playing an increasingly important role.

Reference£º
Patent; Roussel Uclaf; US4254123; (1981); A;,
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