Rationale4,7‐Dichloroquinoline (DCQ) represents a group of synthetic molecules inspired by natural products with important roles in biological and biomedical areas. This work aimed to characterize DCQ and its derivatives by high‐resolution electrospray ionization (ESI) mass spectrometry and tandem mass spectrometry (ESI‐MS/MS), supported by theoretical calculations. Biological assays were carried out with DCQ and its derivatives to determine LC50 values against Aedes aegypti larvae.MethodsFive DCQ derivatives were synthesized by using previously described protocols. ESI‐MS/MS analyses were carried out with a quadrupole/time‐of‐flight and ion‐trap instrument. The proposed gas‐phase protonation sites and fragmentation were supported by density functional theory calculations. The larvicidal tests were performed with the Ae. aegypti Rockefeller strain, and the LC50 values were determined by employing five test concentrations. Larval mortality was determined after treatment for 48 h.ResultsDCQ bromides or aldehydes (C‐3 or C‐8 positions), as well as the trimethylsilyl derivative (C‐3 position), were prepared. Detailed ESI‐MS/MS data revealed heteroatom elimination through an exception to the even‐electron rule, to originate open‐shell species. Computational studies were used to define the protonation sites and fragmentation pathways. High activity of DCQ and its derivatives against Ae. aegypti larvae was demonstrated.ConclusionOur results provided a well‐founded characterization of the fragmentation reactions of DCQ and its derivatives, which can be useful for complementary studies of the development of a larvicidal product against Ae. aegypti.

中文翻译：

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具有杀埃及伊蚊幼虫活性的氯喹啉衍生物电喷雾电离串联质谱裂解机制的表征

基本原理4,7-二氯喹啉（DCQ）代表一组受天然产物启发的合成分子，在生物和生物医学领域发挥着重要作用。这项工作旨在通过高分辨率电喷雾电离 (ESI) 质谱和串联质谱 (ESI-MS/MS) 表征 DCQ 及其衍生物，并得到理论计算的支持。使用 DCQ 及其衍生物进行生物测定以确定 LC50价值观反对埃及伊蚊方法使用先前描述的方案合成了五种 DCQ 衍生物。使用四极杆/飞行时间和离子阱仪器进行 ESI-MS/MS 分析。所提出的气相质子化位点和碎片得到了密度泛函理论计算的支持。杀幼虫试验是用艾。埃及伊蚊洛克菲勒应变和 LC50通过采用五个测试浓度来确定值。处理48小时后测定幼虫死亡率。结果制备了DCQ溴化物或醛（C-3或C-8位）以及三甲基甲硅烷基衍生物（C-3位）。详细的 ESI-MS/MS 数据揭示了通过偶数电子规则的例外消除杂原子，从而产生开壳层物种。计算研究用于定义质子化位点和碎裂途径。 DCQ及其衍生物的高活性艾。埃及伊蚊结论我们的结果为 DCQ 及其衍生物的裂解反应提供了有根据的表征，这对于针对幼虫开发杀幼虫产品的补充研究非常有用。艾。埃及伊蚊。