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Abstract: A copper‐catalyzed one‐pot approach to α‐aryl amidines from terminal alkynes, sulfonyl azides, and aryl sulfonamides via a Truce‐Smiles rearrangement under mild condition in good to excellent yields was reported for the first time. The formation of such aryl‐sp3 C−C bond previously could not be directly achieved by the common method. The stoichiometry of substrates played an important role in improving the yields of desired products. In addition, two sets of signals were observed in the 1H NMR spectra of α‐aryl amidines and their possible cause was investigated by the control experiments as well. [ABSTRACT FROM AUTHOR]

High-performance liquid chromatography coupled with time-of-flight mass spectrometry (HPLC-TOF/MS) and high-performance liquid chromatography-triple quadrupole mass spectrometry (HPLC-QQQ/MS/MS) were utilized to clarify the chemical constituents of Mahuang-Fuzi-Xixin Decoction. There are 52 compounds, including alkaloids, amino acids and organic acids were identified or tentatively characterized by their characteristic high resolution mass data by HPLC-QQQ/MS/MS. In the subsequent quantitative analysis, 10 constituents, including methyl ephedrine, aconine, songrine, fuziline, neoline, talatisamine, chasmanine, benzoylmesaconine, benzoylaconine and benzoylhypaconine were simultaneously determined by HPLC-QQQ/MS/MS with multiple reaction monitoring mode. Satisfactory linearity was achieved with wide linear range and fine determination coefficient ( r > 0.9992). The relative standard deviations (RSD) of inter- and intra-day precisions were <3%. This method was also validated by repeatability, stability and recovery with RSD <3% respectively. A highly sensitive and efficient method was established for chemical constituents studying, including identification and quantification of Mahuang-Fuzi-Xixin decoction. [ABSTRACT FROM AUTHOR]