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.

结到样品液相色谱图以及液相色谱峰应的一级质谱图。谱图进行分析归纳,推测样品中含有四环、差向异构四环和差向异构杂质组分。