Heterocyclic Building Blocks-quinoxaline

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 (301 mg, 1.00 mmol) was condensed with 3-hydroxyquinoxaline-2-carboxylic acid (228 mg, 1.20 mmol) to afford the desired title compound (255 mg, yield 54%) as a pale yellow solid. 1H-NMR (DMSO-d6, 400 MHz) delta: 12.82 (1H, brs), 9.48 (1H, brs), 7.86 (1H, t, J=7.2 Hz), 7.78 (2H, d, J=7.2 Hz), 7.64 (1H, t, J=5.6 Hz), 7.38 (2H, m), 7.18 (2H, m), 4.90 (1H, dd, J=12.4 Hz, 6.0 Hz), 4.84 (1H, m), 4.02-3.90 (2H, m), 3.57-3.20 (2H, m), 2.05 (4H, m), 1.55 (1H, m), 0.95 (6H, d, J=4.8 Hz). LCMS (ESI, m/z): 474 (M+H)+., 1204-75-7

1204-75-7 3-Oxo-3,4-dihydroquinoxaline-2-carboxylic acid 71001, aquinoxaline compound, is more and more widely used in various fields.

Reference£º
Patent; Daiichi Sankyo Company, Limited; EP2258697; (2010); A1;,
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With the rapid development and complex challenges of chemical substances, new drug synthesis pathways are usually the most effective.32601-86-8,2-Chloro-3-methylquinoxaline,as a common compound, the synthetic route is as follows.

To a solution of 2-chloro-3-methylquinoxaline L [45] (1.0 g, 5.6mmol) and 2,4-dichloroaniline (0.91 g, 5.6mmol) in anhydrous DMF (10mL), Cs2CO3 (1.82 g, 5.6mmol) was added under inert atmosphere. The mixture was stirred at 70C for 24h. After cooling, water then CH2Cl2 were added. The organic layer was then washed five times with water and dried with Na2SO4. After filtration and evaporation, the resulting solid was purified by silica gel column chromatography (eluent: Petroleum Ether/CH2Cl2 7/3 then 1/1) to afford N-(2,4-dichlorophenyl)-3-methylquinoxalin-2-amine. Yield 19%. White powder. mp 152C. 1H NMR (250MHz, CDCl3) delta=9.06 (d, J=9.0 Hz, 1H), 7.90 (d, J=8.2 Hz, 1H), 7.83 (d, J=8.2 Hz, 1H), 7.67-7.57 (m, 1H), 7.57-7.30 (m, 4H), 2.78 (s, 3H). 13C NMR (63MHz, CDCl3) delta=147.5, 145.2, 140.4, 138.0, 135.3, 129.6, 128.8, 128.4, 128.0, 127.6, 127.0, 126.4, 123.2, 121.4, 21.1. LC-MS (ESI, 35 eV): tR=5.49min, m/z 304 [M+H]+., 32601-86-8

As the paragraph descriping shows that 32601-86-8 is playing an increasingly important role.

Reference£º
Article; Desroches, Justine; Kieffer, Charline; Primas, Nicolas; Hutter, Sebastien; Gellis, Armand; El-Kashef, Hussein; Rathelot, Pascal; Verhaeghe, Pierre; Azas, Nadine; Vanelle, Patrice; European Journal of Medicinal Chemistry; vol. 125; (2017); p. 68 – 86;,
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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

EXAMPLE 15 2-[(Propylamino)(propylimino)methylthio]-3-quinoxalinecarboxylic acid ethyl ester, hydrochloride 2-Chloro-3-quinoxalinecarboxylic acid ethyl ester (3.551 g., 0.015 mole) and 2.405 g. (0.015 mole) of 1,3-di-n-propylthiourea were dissolved in acetone and heated at reflux for 11/2 hours. The solution was concentrated to a volume of 50 ml. and cooled. A small amount of solid was removed by filtration. The filtrate was further concentrated to a volume of 25 ml. and ether was added to turbidity. After the reaction mixture had been cooled the yellow solid was collected by filtration to give 2.77 g. (46.6%) of the product, m.p. 129-130 C. Analysis for: C18 H25 ClN4 O2 S Calculated: C, 54.47; H, 6.35; N, 14.12; Cl, 8.93; S, 8.08. Found: C, 54.42; H, 6.50; N, 14.12; Cl, 8.87; S, 8.07., 49679-45-0

49679-45-0 Ethyl 3-chloroquinoxaline-2-carboxylate 12283436, aquinoxaline compound, is more and more widely used in various fields.

Reference£º
Patent; American Home Products Corporation; US4349674; (1982); A;,
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879-65-2, 2-Quinoxalinecarboxylic acid is a quinoxaline compound, ?involved in a variety of chemical synthesis. Rlated chemical reaction is continuously updated,879-65-2

Thionyl chloride (1 mL) was added to a solution of 2-quinoxalinecarboxylic acid (125 mg, 0.718 mmol) in methanol (20 mL). The resulting solution was stirred for 3 hours and evaporated to dryness under reduced pressure. The resulting off-white solid was collected (115 mg, 85percent). 1H NMR (400 MHz, CDCl3): delta (ppm) 9.567 (s, 1H, H5), 8.342 (dd, J1-2 = 8 Hz, J1-3 2 Hz, 1H, H1), 8.284 (dd, J4-3 = 8Hz, J4-2 = 0.8 Hz, 1H, H4), 7.938 (q-br, J2/3-3/2/1/4 = 8.4 Hz 2H, H2/3).

The synthetic route of 879-65-2 has been constantly updated, and we look forward to future research findings.

Reference£º
Article; Cowan, Matthew G.; Miller, Reece G.; Brooker, Sally; Supramolecular Chemistry; vol. 27; 11-12; (2015); p. 780 – 786;,
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108229-82-9, 6-Bromo-2,3-dichloroquinoxaline is a quinoxaline compound, ?involved in a variety of chemical synthesis. Rlated chemical reaction is continuously updated

To a solution of compound 1 (2.78 g, 0.01 mol) in DMF (50 mL), 4-(trifluoromethyl)aniline (1.61 g, 0.01 mol) was added. The reaction mixture was refluxed for 24 h. After completion of the reaction, the reaction mixture was poured onto crushed ice with stirring. Then, the solid residue that formed was filtered, washed with water, dried and crystallized from petroleum ether (80-100C) to give 4. Yield: 40%; (brown powder): m.p. 157-159 O C;IR (KBr, cm -1 ): 3158 (NH), 1603 (C=N). 1 H NMR(DMSO-d 6 , delta , ppm): 7.25-7.82 (m, 7H, Ar-H), 9.71(s, br, 1H, NH; exchangeable with D 2 O). 13 C NMR(DMSO-d 6 , delta , ppm): 121.15-147.09 (12Ar-C, CF 3 ),152.69, 152.86 (2C=N). MS (m/z), 336 (M + -C 2 H 3 F 2 ; 100%), 401 (M + ; 88%), 402 (M + + 1; 60%),403 (M + + 2; 57%), 404 (M + + 3; 62%), 405 (M + + 4;52%). Analysis: calcd. for C 15 H 8 BrClF 3 N 3 (402.60):C, 44.75; H, 2.00; N, 10.44%; found: C, 44.61; H,2.26; N, 10.69%.

108229-82-9, 108229-82-9 6-Bromo-2,3-dichloroquinoxaline 13799585, aquinoxaline compound, is more and more widely used in various fields.

Reference£º
Article; Abbas, Hebat-Allah S.; Al-Marhabi, Aisha R. M.; Ammar, Yousry A.; Acta poloniae pharmaceutica; vol. 74; 2; (2017); p. 445 – 458;,
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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.

91-19-0, Quinoxaline (0.65g, 5 mmol), pyruvic acid (1.32g, 15 mmol), AgNO3 (0.068g, 0.4 mmol), (NH4) 2S2O8 (1.71g, 7.5 mmol), CF3CO2H (1.7g, 15 mmol) were dissolved in a 1 : 1 mixture of DCM/H2O (50ml). The reaction mixture was stirred at 40 C. After cooling to room temperature the mixture was extracted with DCM, washed with brine and dried over Mg S04, then evaporated to give 1-quinoxalin-2-yl-ethanone (0. 89g, 100%).

91-19-0 Quinoxaline 7045, aquinoxaline compound, is more and more widely used in various fields.

Reference£º
Patent; F2G LTD; WO2005/92304; (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.59564-59-9,3,4-Dihydroquinoxalin-2(1H)-one,as a common compound, the synthetic route is as follows.

59564-59-9, EXAMPLE 294 4-Methoxycarbonyl-1,2,3,4-tetrahydroquinoxalin-2-one (IV) To 2.99 g of 1,2,3,4-tetrahydroquinoxalin-2-one (IV) in 30 ml of methyl tert-butyl ether are added 2.18 ml of methyl chloroformate. After stirring for 1 hr, 4.9 ml of diisopropylethylamine are added. The reaction is stirred an additional 30 min and then concentrated under reduced pressure. The residue is partitioned between dichloromethane and aq. sodium bicarbonate and the organic layers dried over sodium sulfate and concentrated. The crude product is crystallized from dichloromethane/hexane/ethyl ether to give the title compound, NMR (CDCl3) 3.84, 4.45, 6.87, 7.11, 7.65, 8.27 delta.

As the paragraph descriping shows that 59564-59-9 is playing an increasingly important role.

Reference£º
Patent; The Upjohn Company; US5541324; (1996); A;,
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80636-30-2, 3,3-Dimethyl-3,4-dihydroquinoxalin-2(1H)-one is a quinoxaline compound, ?involved in a variety of chemical synthesis. Rlated chemical reaction is continuously updated,80636-30-2

EXAMPLE 296 3,3-Dimethyl-4-[(1-methyl)ethyl]oxycarbonyl-1,2,3,4-tetrahydroquinoxalin-2-one (IV) To 2.28 g of 4-chlorocarbonyl-3,3-dimethyl-1,2,3,4-tetrahydroquinoxalin-2-one (prepared by the method of Example 32 but using 3,3-dimethyl-1,2,3,4-tetrahydroquinoxalin-2-one rather than 6-fluoro-3,3-dimethyl-1,2,3,4-tetrahydroquinoxalin-2-one) in 25 ml of 2-propanol (the starting material is not all in solution) are added 0.694 g of lithium isopropoxide. After about 1.5 hr the reaction mixture became homogeneous and then again heterogeneous as the product precipitated out. After a total of 2 hr the solvent is removed under reduced pressure and the residue is partitioned between dichloromethane aid saline. The organic layers are dried over sodium sulfate and the filtrate is concentrated. Ether is added and the resulting solid is collected to give the title compound. NMR (CDCl3) 1.28, 1.63, 5.01, 6.80, 6.98-7.11, 7.27, 7.96 delta.

80636-30-2 3,3-Dimethyl-3,4-dihydroquinoxalin-2(1H)-one 595203, aquinoxaline compound, is more and more widely used in various fields.

Reference£º
Patent; The Upjohn Company; US5541324; (1996); A;,
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55687-02-0, 6-Bromo-2-chloroquinoxaline is a quinoxaline compound, ?involved in a variety of chemical synthesis. Rlated chemical reaction is continuously updated

6-bromo, 2-chloroquinoxaline (0.700 g, 2.8 mmol) and Triethylamine (0.87 g, 8.6 mmol) were dissolved in DMSO (15 mL) at room temperature and (f?)-1-(3-Fluoro-phenyl)- ethylamine hydrochloride (0.400 g, 2.8 mmol) was added. The reaction mixture was stirred at RT for 16 hours. After completion of reaction (confirmed by TLC), water (10OmL) was added to the reaction mixture and it was extracted with ethyl acetate (50 mL x 3). The organic layer was washed with water (15 mL), brine (15 mL), and was then dried over Na2SO4. The organic layer was concentrated in vacuo to afford the crude product.The crude product was adsorbed on silica gel and was purified by column chromatography using neutral silica gel of 60-120 mesh size. Methanol (1-1.5 %) was used as a gradient in DCM for elution of the title compound as a solid (0.35 g, 36%)., 55687-02-0

The synthetic route of 55687-02-0 has been constantly updated, and we look forward to future research findings.

Reference£º
Patent; SENTINEL ONCOLOGY LIMITED; BOYLE, Robert, George; WALKER, David, Winter; WO2010/136755; (2010); A1;,
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With the rapid development and complex challenges of chemical substances, new drug synthesis pathways are usually the most effective.55687-02-0,6-Bromo-2-chloroquinoxaline,as a common compound, the synthetic route is as follows.

The title compound was prepared from 6-Bromo-2-chloro-quinoxaline (3 g, 12.32 mmol) using the method applied for example 5 with the following exceptions: (1 ) in step 1 , 1-Methyl-1-phenyl-ethylamine (1.99 g, 14.72 mmol) was used instead of (R)-1 -(3-Fluoro-phenyl)-ethylamine and Nu,Nu-Diisopropylethylamine (8.4 mL, 6.23 g, 48.23 mmol) was used instead of trimethylamine (2) Title product was isolated as the free base. Yield of final step: 0.04 g (41 %)., 55687-02-0

The synthetic route of 55687-02-0 has been constantly updated, and we look forward to future research findings.

Reference£º
Patent; SENTINEL ONCOLOGY LIMITED; BOYLE, Robert George; WALKER, David Winter; (166 pag.)WO2016/170163; (2016); A1;,
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