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Published on: February 2, 2024
Triterpenoids from Eugenia grandis: structure elucidation by NMR spectroscopy
Karuppiah Pillai Manoharan1, Fan Jing Song, Tan Kwong Huat Benny
1Department of Chemistry, National University of Singapore, Science Drive 3, 117543 Singapore.
Magnetic Resonance in Chemistry : MRC
|January 18, 2007
Summary
Researchers identified a new pentacyclic triterpenoid and a rare triterpenoid from Eugenia grandis stem bark. These compounds, along with known ones, represent the first reported phytochemicals from this plant source.
Area of Science:
- Natural Product Chemistry
- Phytochemistry
- Organic Chemistry
Background:
- Eugenia grandis (Syzygium grande) is a plant species with potential but largely unexplored phytochemical constituents.
- Triterpenoids are a diverse class of natural products with a wide range of biological activities.
- Previous phytochemical investigations of Eugenia grandis are limited, necessitating further exploration.
Purpose of the Study:
- To isolate and characterize chemical constituents from the stem bark of Eugenia grandis.
- To identify novel or rarely encountered pentacyclic triterpenoids from this plant source.
- To establish the structures of isolated compounds using advanced spectroscopic methods.
Main Methods:
- Extraction of Eugenia grandis stem bark using chloroform.
- Isolation of compounds via chromatographic techniques.
- Structure elucidation using 1D and 2D Nuclear Magnetic Resonance (NMR) spectroscopy.
Main Results:
- Isolation of a new pentacyclic triterpenoid, 2alpha,3beta-dihydroxylup-12-en-28-oic acid (1).
- Isolation of a rarely encountered pentacyclic triterpenoid, 3beta-hydroxylup-12-en-28-oic acid (2).
- Identification of five known compounds: friedelin (3), 3beta-friedelinol (4), betulinic acid (5), oleanolic acid (6), and beta-sitosterol (7).
Conclusions:
- The study successfully identified and characterized seven compounds from Eugenia grandis stem bark, including one novel and one rare pentacyclic triterpenoid.
- The structural assignments were confirmed through comprehensive NMR spectroscopic analysis.
- This research marks the first report of any isolated compounds from the stem bark of Eugenia grandis.
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