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 20348-09-8 as follows. Safety of 2H-Pyrido[3,2-b][1,4]oxazin-3(4H)-one
a) 3,4-Dihydro-2H-pyrido[3,2-&][l,4]oxazine; To an ice-cold solution of 4H-rhoyrido[3,2-][l,4]oxazin-3-one (5.00 g, 33.3 mmol) in TetaF (40 mL) was added lithium aluminum hydride (66.6 mL of a 1.0 M solution in TetaF, 66.6 mmol). Following the addition, the solution was heated to reflux. After 18 h, the solution was cooled to 00C and quenched the reaction with H2O (4 mL) followed by NaOH (4 mL, 15%) and H2O (10 mL). The resulting slurry was filtered over Celite and the filtrate concentrated to give the title compound (3.87 g, 85%) as a blue-gray powder: 1H NMR (500 MHz, OMSO-d6) delta 7.53 (dd, J= 4.5, 1.0 Hz, IH), 6.90-6.89 (m, IH), 6.61 (br s, IH), 6.44 (dd, J= 8.0, 3.0 Hz, IH), 4.08 (t, J= 4.5 Hz, 2H), 3.39-3.36 (m, 2H); MS (ESI) m/e 31 (M + eta)
According to the analysis of related databases, 20348-09-8, the application of this compound in the production field has become more and more popular.
Reference:
Patent; AFFINIUM PHARMACEUTICALS, INC.; WO2007/53131; (2007); A2;,
Amide – Wikipedia,
Amide – an overview | ScienceDirect Topics