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Anti-Complementary Components of Helicteres angustifolia
Xiang Yin1, Yan Lu2, Zhi-Hong Cheng3
1State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 210009, China. yinxiang2zhy@163.com.
Molecules (Basel, Switzerland)
|November 12, 2016
Summary
Two new compounds and nine known compounds were isolated from Helicteres angustifolia, with eleven showing anti-complementary activity. Compounds 4 and 5 demonstrated potent activity against classical and alternative complement pathways.
Area of Science:
- Natural Product Chemistry
- Pharmacology
- Immunology
Background:
- Helicteres angustifolia is a plant with potential medicinal properties.
- The complement system plays a crucial role in innate immunity and inflammation.
Purpose of the Study:
- To isolate and characterize chemical constituents from the aerial parts of Helicteres angustifolia.
- To evaluate the anti-complementary activity of the isolated compounds.
Main Methods:
- Isolation of compounds using chromatographic techniques.
- Structure elucidation using mass spectrometry (MS) and nuclear magnetic resonance (NMR) spectroscopy.
- Assessment of anti-complementary activity against classical and alternative complement pathways.
Main Results:
- A new phenalenone derivative (1) and two new sesquilignan glycosides (2, 3) were identified, along with nine known compounds (4-12).
- Eleven compounds exhibited anti-complementary activity.
- Compounds 4 and 5 showed potent inhibition of both classical and alternative complement pathways, with specific CH50 and AP50 values reported.
Conclusions:
- Helicteres angustifolia contains diverse chemical structures, including flavonoids and lignans, with significant anti-complementary properties.
- Compounds 4 and 5 are promising candidates for further investigation due to their potent complement inhibitory effects.
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