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.
1-Ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (137 mg, 0.717 mmol) was added to a methylene chloride solution (4.8 ml) of (2S)-3-methyl-1-oxo-1-(4-{[6-(trifluoromethyl)pyridin-3-yl]oxy}piperidin-1-yl)butan-2-amine dihydrochloride (200 mg, 0.478 mmol), 3-hydroxyquinoxaline-2-carboxylic acid (93.7 mg, 0.478 mmol), 1-hydroxybenzotriazole monohydrate (77.5 mg, 0. 574 mmol) and N-methylmorpholine (0.263 ml, 2.39 mmol), at room temperature, and stirring was carried out at room temperature overnight. Water was added to the reaction solution, followed by extraction with methylene chloride, and the extract was washed sequentially with a saturated aqueous sodium hydrogencarbonate solution, water and saline, and dried over anhydrous sodium sulfate. After the organic layer was concentrated and the resulting residue was purified by silica gel column chromatography, the resulting residue was suspended in a mixed solvent of ethanol-diethyl ether, and then the solid substance was collected by filtration to afford the desired title compound (145 mg, yield 59%) as a yellow solid. 1H-NMR (CDCl3, 400 MHz) delta: 12.08 (1H, brs), 10.15 (1H, brs), 8.41 (1H, dd, J=10.6 Hz, 2.7 Hz), 8.02 (1H, brs), 7.66-7.30 (5H, m), 5.09-5.04 (1H, m), 4.78-4.70 (1H, m), 4.10-3.64 (4H, m), 2.35-1.95 (5H, m), 1.14-1.09 (6H, m). IR (KBr) cm-1: 2965, 1685, 1640, 1530, 1340. MS (ESI, m/z): 518 (M+H)+. HRMS (ESI, m/z): 518.2016 (Calcd for C25H27F3N5O4: 518.2015). Anal. Calcd for C25H26F3N5O4¡¤0.5H2O: C, 57.03; H, 5.17; N, 13.30; F, 10.83. Found: C, 56.82; H, 4.98; N, 13.03; F, 10.89., 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;,
Quinoxaline – Wikipedia
Quinoxaline | C8H6N2 | ChemSpider