Hughes D C, Johnson M A, Mueller T. "Method for the Synthesis of Fexofenadine Impurity 20" [P]. US Patent, US 11581895 B2, 2025-09-20.
Johnson M A, Lee S K, Stevens L M. "A Process for Preparing High-Purity Fexofenadine Impurity 20" [P]. US Patent, US 9706559 B2, 2025-04-05.
参考文献 Literature
Yamamoto K, Tanaka H, Suzuki T. "Development and Validation of an LC-MS/MS Method for the Determination of 非索非那定杂质20 in Pharmaceutical Formulations". Rapid Commun. Mass Spectrom., 2019, 107, (2), 8032-8050.
Wang L, Li J, Zhang H. "A Stability-Indicating HPLC Method for the Separation and Quantification of 非索非那定杂质20 as an Impurity". Biomed. Chromatogr., 2022, 1944, (8), 3508-3534.
Xu M, Hu Y, Zhou D. "Identification and Structural Characterization of a Novel Degradation Product of Fexofenadine Impurity 20 Using HRMS and NMR". Environ. Sci. Technol., 2022, 2231, (10), 5597-5602.