Three new indole alkaloids from Trigonostemon lii
Cheng-Jian Tan1, Ying-Tong Di, Yue-Hu Wang
1State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650204, Yunnan, PRC.
Organic Letters
|April 22, 2010
Summary
Three new indole alkaloids, trigonoliimines A-C, were discovered in Trigonostemon lii leaves. Trigonoliimine A demonstrated moderate activity against the human immunodeficiency virus type 1 (HIV-1).
Area of Science:
- Natural Product Chemistry
- Medicinal Chemistry
- Organic Chemistry
Background:
- The plant Trigonostemon lii is a source of novel chemical compounds.
- Indole alkaloids represent a diverse class of natural products with significant biological activities.
- Exploring new chemical entities from natural sources is crucial for drug discovery.
Purpose of the Study:
- To isolate and characterize unprecedented indole alkaloids from Trigonostemon lii.
- To elucidate the unique polycyclic structures of the isolated compounds.
- To evaluate the anti-HIV-1 activity of the novel alkaloids.
Main Methods:
- Isolation of compounds using chromatographic techniques.
- Structure determination via spectroscopic methods (NMR, MS) and computational analysis.
- Confirmation of stereochemistry using Circular Dichroism (CD) exciton chirality.
Main Results:
- Three new indole alkaloids, named trigonoliimines A-C (1-3), were successfully isolated.
- These compounds possess a unique and complex polycyclic system.
- Trigonoliimine A exhibited modest anti-human immunodeficiency virus type 1 (HIV-1) activity with an EC(50) of 0.95 microg/mL and a therapeutic index (TI) of 7.9.
Conclusions:
- The study reports the discovery of three novel indole alkaloids from Trigonostemon lii.
- The structural elucidation confirmed a unique polycyclic framework for these compounds.
- Trigonoliimine A shows potential as a lead compound for further anti-HIV-1 drug development.
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