SYNTHESIS OF POTENTIAL IMPURITIES OF CEFALEXIN AND CEFRADINE

The synthesis of some impurities of the cephalosporin antibiotics cefa lexin and cefradine is described. These impurities which may be presen t in commercial samples are formed during the semi-synthetic preparati on of these antibiotics or upon their degradation. The preparation of these compounds enables the validation of selective quantitative analy tical methods, such as column liquid chromatography and thin layer chr omatography.