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Cardenolides from Ornithogalum boucheanum
1Institut für Pharmakognosie der Universität Wien, Währingerstr. 25, A-1090 Wien, Austria.
Planta Medica
|April 1, 1987
Summary
This study isolated and identified eight cardenolides from Ornithogalum boucheanum, including novel compounds and unusual sugar combinations like apiose in cardiac glycosides.
Area of Science:
- Phytochemistry
- Natural Product Chemistry
- Pharmacognosy
Background:
- Ornithogalum species are known sources of bioactive compounds.
- Cardenolides are a class of cardiac glycosides with significant pharmacological potential.
- Understanding the chemical diversity of Ornithogalum species is crucial for drug discovery.
Purpose of the Study:
- To isolate and characterize cardenolides from Ornithogalum boucheanum.
- To identify the specific genins and sugar moieties of the isolated cardenolides.
- To report novel occurrences of cardenolides and their structural features.
Main Methods:
- Isolation using column chromatography and droplet counter-current chromatography.
- Structure elucidation via Nuclear Magnetic Resonance (NMR) spectroscopy (1H-NMR, 13C-NMR) and Mass Spectrometry (MS) (EI-MS, LD-MS).
- Hydrolysis (acid/enzymatic) followed by Thin-Layer Chromatography (TLC) and Gas Chromatography (GC) for genin and sugar identification.
Main Results:
- Eight cardenolides were isolated and identified.
- First report of 15beta, 16alpha-dihydroxyuzarigenin.
- First description of syriogenin, uzarigenin, and digitoxigenin genins in the Ornithogalum genus.
- Unusual occurrence of three different monosaccharides and apiose in cardenolides.
Conclusions:
- Ornithogalum boucheanum is a rich source of structurally diverse cardenolides.
- The presence of apiose in cardiac glycosides is reported for the first time.
- These findings expand the known chemical profile of Ornithogalum and cardiac glycosides.
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