New pyridocarbazole alkaloids from Strychnos nitida
Wei Li1, Gui-Hua Tang1, Lin Chen1
1a School of Pharmaceutical Sciences , Sun Yat-sen University , Guangzhou , China.
Natural Product Research
|October 13, 2017
Summary
Researchers identified novel pyridocarbazole alkaloids, (±)-stritidas A-C, from Strychnos nitida. Compounds 2 and 3 are the first pyridocarbazoles with an N-2-hydroxyethyl group, confirmed by spectroscopic and chemical analyses.
Area of Science:
- Natural Product Chemistry
- Phytochemistry
- Organic Chemistry
Background:
- Strychnos nitida is a plant species known for its diverse phytochemical constituents.
- Pyridocarbazole alkaloids represent a class of natural products with potential biological activities.
- Previous research on Strychnos species has identified various indole alkaloids.
Purpose of the Study:
- To conduct a phytochemical investigation of Strychnos nitida.
- To isolate and characterize new chemical compounds from the plant.
- To identify novel pyridocarbazole alkaloids and explore their structural features.
Main Methods:
- Extraction and isolation of compounds from Strychnos nitida.
- Structure elucidation using comprehensive spectroscopic techniques (MS, UV, IR, NMR).
- Application of chemical methods for structural confirmation.
Main Results:
- Isolation of three new racemic pyridocarbazole alkaloids, designated (±)-stritidas A-C (1-3).
- Identification of three known monoterpenoid indole alkaloids (4-6).
- Compounds 2 and 3 were characterized as the first examples of pyridocarbazole alkaloids containing an N-2-hydroxyethyl moiety.
Conclusions:
- The phytochemical investigation of Strychnos nitida yielded novel pyridocarbazole alkaloids.
- The structural determination confirmed the presence of a unique N-2-hydroxyethyl group in compounds 2 and 3.
- This study expands the known structural diversity of pyridocarbazole alkaloids.
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