epimer

1.It elaborates the definitions of epimer and epimerization, states the applications of epimerization in medicine and pesticide,and points out its expansive prospect .

阐述了差向体和差向的定义。差向技术在医药和农药中间体中应用广,前景广阔。

2.RESULTS The chlortetracycline's epimer, tetracycline and its epimer, as impurities in chlortetracycline have been determined by the liquid chromatogram and its first order mass spectrum.

结果得到金霉素样品液相以及液相峰对应的一级质。对进行分析归纳,推测金霉素样品中含有四环素、差向四环素和差向金霉素杂质组分。