Indole Alkaloids from Alstonia angustifolia
1Organisch-chemisches Institut der Universität Zürich, Winterthurerstraße 190, CH-8057 Zürich, Switzerland.
Planta Medica
|October 1, 1989
Summary
Researchers isolated eleven alkaloids from Alstonia angustifolia stem bark, including seven known compounds and four novel alkaloids. Structural elucidation was achieved through spectroscopic analysis and chemical correlation.
Area of Science:
- Natural Product Chemistry
- Phytochemistry
- Organic Chemistry
Background:
- Alstonia angustifolia is a plant species known for its rich alkaloid content.
- Previous research has identified various alkaloids from different parts of Alstonia species.
- The stem bark of Alstonia angustifolia has not been extensively studied for its alkaloid profile.
Purpose of the Study:
- To isolate and identify alkaloids from the stem bark of Alstonia angustifolia.
- To characterize novel alkaloid structures and compare them with known compounds.
- To contribute to the understanding of the chemical diversity within the Alstonia genus.
Main Methods:
- Extraction of alkaloids from Alstonia angustifolia stem bark.
- Isolation of individual alkaloid compounds using chromatographic techniques.
- Structure determination through comprehensive spectroscopic analysis (e.g., NMR, MS) and chemical correlation.
Main Results:
- Eleven alkaloids were successfully isolated from the plant material.
- Seven known alkaloids were identified: echitamine, N(b)-demethylechitamine, pseudoakuammigine, tubotaiwine, akuammicine, N(b)-beta-methylantirhine, and N(b)-methylakuammidine.
- Four new alkaloids were discovered: pseudoakuammigine N-oxide, akuammicine N-oxide, N(b)-demethylalstogustine, and N(b)-demethylalstogustine N-oxide.
Conclusions:
- The stem bark of Alstonia angustifolia is a source of diverse indole alkaloids.
- The identification of novel alkaloids expands the known chemical repertoire of this plant species.
- Spectroscopic and chemical methods are effective for elucidating alkaloid structures.
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