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

阐述了差向异体和差向异的定义。差向异术在医药和农药中体中应用泛,前景。

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.

果得到金霉素样品液相色谱图以及液相色谱峰对应的一级质谱图。对谱图进行分析归纳,推测金霉素样品中含有四环素、差向异四环素和差向异金霉素杂质组分。