Identification of impurities in macrolides by liquid chromatography-mass spectrometric detection and prediction of retention times of impurities by constructing quantitative structure-retention relationship (QSRR).

•The characteristics of impurities in macrolides were summarized to guide the impurity analysis of this class of drugs.•Three separate LC-ESI–MS/MS methods were developed to investigate impurities in the three 16-membered ring macrolides.•A QSRR model was constructed by MLR to predict the retention times of identified impurities which were not detected–MS methods without obtaining their reference standards.