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Enzymatic Synthesis of Epoxidized Metabolites of Docosahexaenoic, Eicosapentaenoic, and Arachidonic Acids
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Thermolides D and E: Total Synthesis and Stereochemical Revision
Wenquan Peng1, Feipeng Han1, Junyang Liu2
1State Key Laboratory of Chemical Oncogenomics, Peking University Shenzhen Graduate School, Shenzhen 518055, China.
Organic Letters
|June 17, 2025
Summary
Researchers synthesized thermolide D diastereomers and thermolide E, confirming structures using NMR and HPLC. This stereochemical strategy aids future fungal polyketide identification.
Area of Science:
- Organic Chemistry
- Natural Product Synthesis
- Chemical Biology
Background:
- Fungal polyketides represent a class of natural products with diverse biological activities.
- Structural elucidation of complex fungal metabolites like thermolides is crucial for understanding their function.
- Stereochemical complexity often challenges the accurate determination of natural product structures.
Purpose of the Study:
- To achieve the total synthesis of thermolide D diastereomers and thermolide E.
- To confirm the proposed structures of thermolides D and E through rigorous analytical methods.
- To establish a reliable stereochemical framework for the structural determination of related fungal polyketides.
Main Methods:
- Application of stereochemical insights and synthetic chemistry principles.
- Total synthesis of target molecules.
- Nuclear Magnetic Resonance (NMR) spectroscopy for structural analysis.
- High-Performance Liquid Chromatography (HPLC) for purity assessment and coelution studies.
Main Results:
- Successful total synthesis of two diastereomers of thermolide D.
- Synthesis and structural confirmation of thermolide E.
- Confirmation of structures by comparing NMR spectra of synthetic and natural products.
- Demonstration of coelution on HPLC, validating the identity of synthetic and natural compounds.
Conclusions:
- The structures of thermolides D and E have been unequivocally confirmed.
- The developed stereochemical approach offers a robust methodology for future structural investigations of fungal polyketides.
- This work contributes to the understanding of fungal secondary metabolism and provides access to valuable natural product analogs.
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