Lycopodium alkaloids (LAs) are the characteristic metabolites of club mosses. Chemical differences often exist in different specimens of a single plant species collected from different geographic origins. In this study, a preliminary LC-MS detection and dereplication analyses of alkaloidal constituents of Lycopodium cernuum var. sikkimense (Müll. Hal.) C.B. Clarke (LCVS2) collected from Fujian province led to the isolation and characterization of three undescribed LAs, lycocernuskines A-C, and six known cernuane-type LAs. The known compounds were previously isolated from the same plant species (LCVS1) collected from Chongqing, and so their dereplication in LCVS2 was accomplished based on their retention times (tR) and the quasi-molecular ion peaks in the LC-MS fingerprint. Chemical structures were identified by spectroscopic methods, single-crystal X-ray diffraction analysis, and electronic circular dichroism calculations. Lycocernuskines A and B are the first two examples of C-12 hydroxylated phlegmarane-type LAs bearing a nitrone residue at the quinoline ring. The isolates were evaluated for their anti-AChE and neuroprotective effects.

中文翻译：

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LC-MS 引导石松石松生物碱的分离和去复制。不同地理起源的锡金语

石松生物碱 (LA) 是苔藓的特征代谢物。从不同地理来源收集的单一植物物种的不同标本中通常存在化学差异。在本研究中，对石松的生物碱成分进行了初步 LC-MS 检测和去重复分析。从福建省收集的 sikkimense (Müll. Hal.) CB Clarke (LCVS2) 导致了三种未描述的 LA、lycocernuskine AC 和六种已知的 cernuane 型 LA 的分离和表征。已知化合物之前是从重庆采集的相同植物物种 (LCVS1) 中分离出来的，因此它们在 LCVS2 中的去复制是基于它们的保留时间 (tR) 和 LC-MS 指纹中的准分子离子峰完成的。通过光谱方法鉴定化学结构，单晶 X 射线衍射分析和电子圆二色性计算。Lycocernuskine A 和 B 是在喹啉环上带有硝酮残基的 C-12 羟基化木质素型 LA 的前两个例子。评估了分离物的抗 AChE 和神经保护作用。