Identification, Quantification, and StereoselectiveDegradation of Triazole Fungicide Cyproconazole in Two Matrixes throughChiral Liquid Chromatography-Tandem Mass Spectrometry

Systematic investigation of cyproconazole, including absolute stereochemistry, fungicidal activity, quantification in two matrices, and stereoselective degradation in cucumber, are conducted in this study. By virtue of the vibrational circular dichroism (VCD) spectroscopy, absolute configurations of four stereoisomers were identified to be (2R, 3R)-(+)-, (2R, 3S)-(+)-, (2S, 3S)-(-)-, and (2S, 3R)-(-)-cyproconazoles. Then, four stereoisomers exhibited stereoselective fungicidal activities against Fusarium graminearum Schw and Magnaporthe oryzae, and the order of fungicidal activity was (2S, 3S)-(-)-stereoisomer ˃ the stereoisomer mixture ˃ (2S, 3R)-(-)-stereoisomer ˃ (2R, 3R)-(+)-stereoisomer ˃ (2R, 3S)-(+)-stereoisomer. Moreover, chiral liquid chromatography-tandem mass spectrometry was used to identify and quantify cyproconazole stereoisomers in soil and cucumber matrices. Good linearity (R2 ≥ 0.99) and recoveries (86.79-92.47%, RSD ≤ 3.94%) for them were achieved, respectively. Furthermore, stereoselect...