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Advanced Structure Analysis Reveals a Transient Portimine B Hydrate.
Jared S Wood1, Junchen Tang2, Wendy K Strangman1
1Department of Chemistry and Biochemistry, University of North Carolina Wilmington, Wilmington, North Carolina 28409, United States.
Journal of Natural Products
|July 25, 2024
Summary
Portimine B, a natural product from Vulcanodinium rugosum, was structurally clarified. New NMR data and calculations reveal its structure differs from portimine A due to a transient hydrate, not an open ring.
Area of Science:
- Marine natural products chemistry
- Organic chemistry
- Computational chemistry
Background:
- Portimine B was isolated from the dinoflagellate Vulcanodinium rugosum.
- Previous studies suggested portimine B has an open tetrahydrofuranyl ring, unlike portimine A.
- Recent synthesis indicated both compounds possess intact tetrahydrofuranyl rings.
Purpose of the Study:
- To definitively determine the structure of portimine B.
- To elucidate the structural divergence between portimine A and portimine B.
- To investigate the role of transient hydrates in structural determination.
Main Methods:
- Nuclear Magnetic Resonance (NMR) spectroscopy, including i-HMBC experiments.
- Advanced density functional theory (DFT) calculations.
- Analysis of natural product extracts from Vulcanodinium rugosum.
Main Results:
- The structural divergence between portimine A and B is attributed to a transient hydrate.
- NMR data and DFT calculations confirm the presence of an intact tetrahydrofuranyl ring in portimine B.
- Clarified the structural ambiguity surrounding portimine B.
Conclusions:
- Portimine B possesses an intact tetrahydrofuranyl ring, consistent with portimine A.
- The transient hydrate is key to understanding the apparent structural differences observed in initial studies.
- This work refines the structural understanding of portimine B and related compounds.
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