Three lycodine-type Lycopodium alkaloids (1–3) were isolated from Lycopodiastrum casuarinoides. Their structures were elucidated by spectroscopic analysis, single-crystal X-ray crystallography, and computational methods. Compound 1 possesses a rearranged five-membered ring D resulting from C-8/C-15 cleavage and a new C-7/C-15 linkage. Compound 2 is the first Lycopodium alkaloid found to bear an additional carbon (C-17) directly bonded to C-8, which is particularly unusual from a biogenetic point of view. Compounds 1–3 were evaluated for acetylcholinesterase inhibitory activities.

中文翻译：

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Lycocasuarines A-C，石松从生物碱Lycopodiastrum casuarinoides

三lycodine型石松生物碱（1 - 3）从分离Lycopodiastrum casuarinoides。通过光谱分析，单晶X射线晶体学和计算方法阐明了它们的结构。化合物1具有因C-8 / C-15裂解和新的C-7 / C-15键合而重排的五元环D。化合物2是第一个被发现带有直接与C-8结合的碳（C-17）的石蒜碱生物碱，从生物遗传学的角度来看，这是特别不寻常的。化合物1 - 3为乙酰胆碱酯酶抑制活性进行评价。