一步法制备羧甲基茯苓多糖的工艺研究

本实验对在有机溶剂中一步法半合成羧甲基茯苓多糖的合成条件进行了研究。结果表明,乙醇是作为羧甲基化反应的合适介质。反应温度提高能加快反应速度;反应时间延长能提高取代度。茯苓多糖葡萄糖当量与氢氧化钠和一氯乙酸的摩尔比调配适当,能减少副产物羟乙酸钠的产生。

Preparation of Carboxymethyl Pachmaran in One Step

The condition for preparation of carboxymethyl pachmaran in one-step in organic solvent medium was studied in this paper.Results are showed as follows.Ethanol is the best medium for the reaction of carboxyl methylation.When the concentration of ethanol is 80%,there is the highest degree of substitution of carboxymethyl.The reaction speed increases as the reaction temperature is raised;the degree of substitution increases as reaction time extends.If the glucose equivalent weight and the molar rate of sodium hydroxide and chloroacetic acid are prepared appropriately,the by-product,sodium carbonylcetate,will occur less.Compared with other methods,one step method for preparation of carboxymethyl pachmaran is easier to operate with a smaller operation volume and consume less water and organic solvent medium.With this method,the degree of substitution of carboxymethyl is high and the water-solubility is good with solubility more than 6 g/100 mL in water.