10.5% |
With sodium hydroxide; In ethanol; water; at 55℃; for 75h; |
500mL three-necked flask, followed by adding 20g <strong>[17902-23-7]tegafur</strong>, 29g gimeracilToAnd 1g of sodium hydroxide, then add 180g of ethanol and 120g of water, open stirring, warmed to 55 , the solution is a clear and transparent system, the reaction was incubated 75h. After the reaction was completed, the mixture was concentrated under reduced pressure at 40 C, ethanol was distilled off, 200 g of water was added to the residue, and the mixture was heated to 60 C to continue the reaction for 4 hours. After the reaction, continue to cool to room temperature, filtered, the filter cake was collected.50 blast oven drying 8h, 35g powdery solid. Will be above35g solid was added to 300mL dichloromethane, heated to reflux 2h, cooled to room temperature, filtered, the filter cake was collected, and dried at 50 C 2h to give a solid about 34g. Take a small amount of solid, dissolved in methanol, TLC detection (developing solvent ethyl acetate: acetic acid = 50: 1), iodine color, the solid contains only BCB and gimeracil. The solid silica gel column chromatography, the choice of 200 ~ 300 mesh silica gel, the amount of silica gel sample weight of 50 times, the eluent is ethyl acetate and acetic acid, wherein ethyl acetate: acetic acid = 50: 1 (volumeratio). BCB was separated by column chromatography and weighed after drying about 3.8g, yield 10.5%, HPLC purity 99.75%. |