应用四甲基氢氧化铵控制电渗流的毛细管电泳方法分离多沙唑嗪及其中间体的对映体

建立了毛细管电泳手性分离多沙唑嗪中间体对映体的方法,并同时分离了多沙唑嗪对映体。考察了不同种类季铵盐对电渗流及分离的影响,其中四甲基氢氧化铵(TMB)能有效控制电渗流并提高组分的分离度。实验还考察了其他因素,如pH值、分离电压和磷酸二氢钠浓度对分离的影响。所用的毛细管为40 cm(有效长度30 cm)×50 μm,缓冲液为12 mmol/L β-环糊精、30 mmol/L TMB、60 mmol/L 磷酸二氢钠(pH 2.2),分离电压为20 kV。在此条件下多沙唑嗪及其中间体的对映体均达到了基线分离。实验结果表明,一些用β-环糊精不能完全分离的对映体通过加入TMB控制电渗流能达到满意的分离效果。     

Synthesis and Crystal Structure of o-Methylisourea Hydrosulfate

l INTRODUCTION As an important and capital intermediate of chemi- cal engineering, medicine and pesticide, o-methyli- sourea today is mainly used to synthesize fluoracil antitumor drugs, pesticides and polyantibacterials. According to the applications and syntheses, o- methylisourea is usually prepared as its salts and es- ters, such as o-methylisourea hydrosulfate, o-me- thylisourea sulfate, o-methylisourea acetate, o-methy- lisourea formate, and so on, since o-methylisourea is unstable.…