| 摘要 |
NEW MATERIAL:A quinoxalinone derivative expressed by the formula (R1 and R2 are methyl, ethyl or propyl; R3 is Cl or azido). EXAMPLE:3, 4-Dihydro-6, 7-dimethoxy-4-methyl-3-oxo-quinoxaline-2-carbonl chlori de. USE:A fluorescent labeling reagent, utilizable for analyzing hydroxyl group- containing compounds and capable of readily carrying out fluorescent labeling of hydroxyl groups and performing analysis with high sensitivity. PREPARATION:For example, a 4,5-dialkoxy-1,2-diaminobenzene is reacted with an alpha-ketomalonic acid in a strong acid and then methylation by diazomethane is carried out. The resultant ester is then hydrolyzed with an alkali and reacted with thionyl chloride to give the compound expressed by formula I (R3 is Cl), which is further reacted with sodium azide to afford the compound expressed by formula I (R3 is azido). |
