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Applications of Liquid-Chromatography Tandem Mass Spectrometry in Natural Products Research: Tropane Alkaloids as a Case Study
Published on: March 8, 2024
Casuarinines A-J, lycodine-type alkaloids from Lycopodiastrum casuarinoides
1Department of Natural Products Chemistry, School of Pharmacy, Fudan University, No. 826 Zhangheng Road, Shanghai 201203, People's Republic of China.
Journal of Natural Products
|August 15, 2013
Summary
Ten new lycodine alkaloids were isolated from Lycopodiastrum casuarinoides. One compound showed neuroprotective effects, while others inhibited acetylcholinesterase.
Area of Science:
- Natural Product Chemistry
- Medicinal Chemistry
- Pharmacology
Background:
- Lycopodiastrum casuarinoides is a plant source of bioactive alkaloids.
- Lycodine alkaloids represent a complex class of natural products with diverse structures.
- Understanding the chemical diversity and biological activities of these alkaloids is crucial for drug discovery.
Purpose of the Study:
- To isolate and characterize new lycodine-type alkaloids from Lycopodiastrum casuarinoides.
- To investigate the neuroprotective and enzyme inhibitory activities of the isolated compounds.
- To propose a biosynthetic pathway for a novel alkaloid structure.
Main Methods:
- Isolation of alkaloids using chromatographic techniques.
- Structure elucidation using spectroscopic methods (NMR, MS) and chemical transformations.
- In vitro assays for neuroprotection (H₂O₂-induced damage in SH-SY5Y cells) and acetylcholinesterase (AChE) inhibition.
Main Results:
- Ten new lycodine alkaloids (casuarinines A-J) and eight known analogues were identified.
- Casuarinines A-D and J possess typical lycodine structures; E-H are piperidine ring cleavage products.
- Casuarinine I features a unique five-membered tetrahydropyrrole ring.
- Casuarinine H demonstrated significant neuroprotection against oxidative stress.
- Casuarinines C and I exhibited moderate AChE inhibitory activity.
Conclusions:
- The study expands the known chemical diversity of lycodine alkaloids.
- Casuarinine H shows promise as a neuroprotective agent.
- Casuarinines C and I are potential leads for developing AChE inhibitors.
- A plausible biosynthetic pathway for the novel casuarinine I was proposed.
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