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Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
Published on: July 17, 2020
Four new phenanthrenes from Monomeria barbata Lindl
Minghui Yang1, Le Cai, Zhigang Tai
1Key Laboratory of Medicinal Chemistry for Nature Resource, Ministry of Education, School of Chemical Science and Technology, Yunnan University, Kunming 650091, PR China.
Fitoterapia
|July 6, 2010
Summary
New biphenanthrene and triphenanthrene compounds from Monomeria barbata Lindl. show significant cytotoxic effects against liver and leukemia cancer cell lines and potent antioxidant activity.
Area of Science:
- Natural Products Chemistry
- Medicinal Chemistry
- Pharmacology
Background:
- Monomeria barbata Lindl. is a plant source of bioactive compounds.
- Phenanthrene derivatives are known for their diverse biological activities.
Purpose of the Study:
- To isolate and characterize new phenanthrene compounds from Monomeria barbata Lindl.
- To evaluate the cytotoxic and antioxidant activities of isolated compounds.
Main Methods:
- Isolation of compounds using chromatographic techniques.
- Structure elucidation using 1D-, 2D-NMR, and HR-ESI-MS.
- In vitro cytotoxic assays against HepG-2, HL60, Skov-3, and A431 cell lines.
- DPPH radical scavenging assay for antioxidant activity.
Main Results:
- Three new biphenanthrene compounds (1-3) and one triphenanthrene compound (4) were isolated.
- Compounds 1-4 demonstrated significant cytotoxic activity against HepG-2 and HL60 cancer cell lines.
- Compounds 1-4 exhibited potent antioxidant activity in the DPPH assay.
Conclusions:
- Monomeria barbata Lindl. is a valuable source of novel phenanthrene derivatives.
- The isolated compounds possess promising cytotoxic and antioxidant properties for further investigation.
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