甲脲是新工艺路线合成可可豆碱的主要原料之一,由尿素和甲胺合成其主要杂质是未反应的尿素和多取代脲。关于尿素及其烷基取代衍生物用薄层色谱法分离及鉴定,国外已有报导;R.W.Relser 介绍了用气相色谱法测定取代脲的方法,但实验条件较难掌握,常有样品分解发生;国内生 Methyl urea is one of the main raw materials for the synthesis of cocoa butter base in the new process route. The main impurities synthesized from urea and methylamine are unreacted urea and multi-substituted urea. For the separation and identification of urea and its alkyl substituted derivatives by thin layer chromatography, it has been reported in foreign countries; RWRelser introduced the method of determining the substituted urea by gas chromatography. However, the experimental conditions are difficult to grasp and the sample decomposition often occurs. Domestic students