New phenanthrenes and stilbenes from Dendrobium loddigesii
Masanobu Ito1, Keiichi Matsuzaki, Jue Wang
1Research Unit of Pharmacognosy, School of Pharmacy, Nihon University, 7-7-1 Narasinodai, Funabashi, Chiba 274-8555, Japan.
Chemical & Pharmaceutical Bulletin
|May 13, 2010
Summary
New phenanthrenes from Dendrobium loddigesii show potent inhibition of nitric oxide (NO) production. These compounds, including loddigesiinols A and B, offer potential for developing new anti-inflammatory agents.
Area of Science:
- Natural Product Chemistry
- Pharmacology
Background:
- Dendrobium loddigesii (Orchidaceae) is a source of bioactive compounds.
- Nitric oxide (NO) plays a crucial role in inflammatory processes.
Purpose of the Study:
- To isolate and characterize new phenanthrenes and stilbenes from Dendrobium loddigesii.
- To evaluate the inhibitory activities of these compounds against NO production and DPPH radical scavenging.
Main Methods:
- Extraction of Dendrobium loddigesii using 80% ethanol.
- Structure elucidation of isolated compounds using spectroscopic studies.
- Assay of inhibitory activity against NO production and DPPH radical scavenging.
Main Results:
- Isolation of new phenanthrenes (loddigesiinols A and B) and stilbenes (loddigesiinols C and D).
- Phenanthrenes and dihydrophenanthrenes demonstrated significant NO production inhibition.
- Loddigesiinol A (1) and B (7) exhibited potent NO inhibitory activity with IC50 values of 2.6 and 10.9 μM, respectively.
- Loddigesiinol D (9) showed weak NO inhibitory activity (IC50 = 69.7 μM).
Conclusions:
- New phenanthrenes from Dendrobium loddigesii possess significant nitric oxide inhibitory properties.
- These findings suggest potential therapeutic applications for these compounds in managing inflammatory conditions.
- Further research into the structure-activity relationship of these phenanthrenes is warranted.
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