Biotransformation processes of fluopyram (FLP), a new succinate dehydrogenase inhibitor (SDHI) fungicide, were investigated by electrochemistry (EC) coupled online to liquid chromatography (LC) and electrospray mass spectrometry (ESI-MS). Oxidative phase I metabolite production was achieved using an electrochemical flow-through cell equipped with a boron-doped diamond (BDD) electrode. Structural elucidation and prediction of oxidative metabolism pathways were assured by retention time, isotopic patterns, fragmentation, and accurate mass measurements using EC/LC/MS, LC-MS/MS, and/or high-resolution mass spectrometry (HRMS). The results obtained by EC were compared with conventional in vitro studies by incubating FLP with rat and human liver microsomes (RLM, HLM). Known phase I metabolites of FLP (benzamide, benzoic acid, 7-hydroxyl, 8-hydroxyl, 7,8-dihydroxyl FLP, lactam FLP, pyridyl acetic acid, and Z/E-olefin FLP) were successfully simulated by EC/LC/MS. New metabolites including an imide, hydroxyl lactam, and 7-hydroxyl pyridyl acetic acid oxidative metabolites were predicted for the first time in our study using EC/LC/MS and liver microsomes. We found oxidation by dechlorination to be one of the major metabolism mechanisms of FLP. Thus, our results revealed that EC/LC/MS-based metabolic elucidation was more advantageous on time and cost of analysis and enabled matrix-free detection with valuable information about the mechanisms and intermediates of metabolism processes.

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通过在线耦合到液相色谱（LC）和电喷雾质谱（ESI-MS）的电化学（EC）研究了新型琥珀酸脱氢酶抑制剂（SDHI）杀菌剂氟吡草胺（FLP）的生物转化过程。使用配备了硼掺杂金刚石（BDD）电极的电化学流通池可实现氧化I相代谢产物的生产。保留时间，同位素模式，碎片和使用EC / LC / MS，LC-MS / MS和/或高分辨率质谱（HRMS）进行的精确质量测量可确保结构阐明和氧化代谢途径的预测。通过将FLP与大鼠和人的肝微粒体（RLM，HLM）进行孵育，将EC获得的结果与常规的体外研究进行了比较。FLP的已知I相代谢产物（苯甲酰胺，苯甲酸，7-羟基，8-羟基，7，通过EC / LC / MS成功模拟了8-二羟基FLP，内酰胺FLP，吡啶基乙酸和Z / E-烯烃FLP）。在我们的研究中，首次使用EC / LC / MS和肝微粒体预测了包括酰亚胺，羟基内酰胺和7-羟基吡啶基乙酸氧化代谢产物的新代谢产物。我们发现脱氯氧化是FLP的主要代谢机制之一。因此，我们的研究结果表明，基于EC / LC / MS的代谢阐明方法在分析的时间和成本上更为有利，并且能够进行无基质检测，并获得有关代谢过程机理和中间体的宝贵信息。在本研究中，我们首次使用EC / LC / MS和肝微粒体预测了7-羟基吡啶基乙酸氧化代谢产物。我们发现脱氯氧化是FLP的主要代谢机制之一。因此，我们的研究结果表明，基于EC / LC / MS的代谢阐明方法在分析的时间和成本上更为有利，并且能够进行无基质检测，并获得有关代谢过程机理和中间体的宝贵信息。在本研究中，我们首次使用EC / LC / MS和肝微粒体预测了7-羟基吡啶基乙酸氧化代谢产物。我们发现脱氯氧化是FLP的主要代谢机制之一。因此，我们的研究结果表明，基于EC / LC / MS的代谢阐明方法在分析的时间和成本上更为有利，并且能够进行无基质检测，并获得有关代谢过程机理和中间体的宝贵信息。

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