Isolation, Synthesis, and Identification of Process‐Related Impurities From Morinidazole

ABSTRACT Morinidazole belongs to the category of third‐generation nitroimidazole antibacterial drugs. In the course of morinidazole production, the mother liquor from the recrystallization process was subjected to analysis for the identification and detection of eight process‐related impurities through high‐performance liquid chromatography (HPLC). The eight impurities ( Imp‐A , Imp‐B , Imp‐C , Imp‐D , Imp‐E , Imp‐F , Imp‐G , and Imp‐H ) included three new impurities ( Imp‐A , Imp‐B , and Imp‐C ) that were previously unreported and one potential genotoxic impurity ( Imp‐H ). Purity separation from the recrystallization mother liquor was carried out using preparative HPLC. To characterize these eight process‐related impurities, high‐resolution mass spectrometry and nuclear magnetic resonance (NMR) spectroscopy were utilized, followed by direct synthesis. The retention times of the impurities were confirmed through co‐injection via HPLC. Additionally, Imp‐B , Imp‐C , and Imp‐G were detected in commercial morinidazole products. A detailed discussion was conducted on the possible pathways leading to the formation of these impurities. Furthermore, the toxicities of these compounds were predicted using ADMET/PK property prediction software based on artificial intelligence algorithm—ADMET Predictor. These results will provide technical support for the quality control of morinidazole.