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Total synthesis of (±)-auranthine confirmed its refined structure
Marie Reinker1, Svetlana A Kalinina2, Dmitrii V Kalinin1
1Institute of Pharmaceutical and Medicinal Chemistry, University of Münster Corrensstraße 48 Münster 48149 Germany dmitrii.kalinin@uni-muenster.de.
RSC Advances
|January 5, 2024
Summary
Researchers confirmed the structure of fungal benzodiazepine auranthine through total synthesis. This study disproved previous proposals, establishing auranthine as a fused quinazolino benzodiazepine dione with a nitrile group.
Area of Science:
- Natural Product Chemistry
- Organic Synthesis
- Mycology
Background:
- Auranthine is a fungal metabolite isolated from *Penicillium aurantiogriseum*.
- The precise structure of auranthine has been a subject of scientific inquiry.
- Benzodiazepines are a class of psychoactive drugs, and fungal-derived analogs are of interest.
Purpose of the Study:
- To elucidate and confirm the definitive structure of natural (-)-auranthine.
- To challenge and disprove previously proposed structural models of auranthine.
- To provide a synthetic route to auranthine for further investigation.
Main Methods:
- Total synthesis of racemic (±)-auranthine.
- Spectroscopic analysis (e.g., NMR, MS) for structural confirmation.
- Comparison of synthetic and natural product data.
Main Results:
- Successful synthesis of (±)-auranthine validated the proposed refined structure.
- The natural (-)-auranthine was confirmed as a fused quinazolino benzodiazepine dione.
- The presence of an acyclic aliphatic nitrile moiety was established, refuting prior structural hypotheses.
Conclusions:
- The total synthesis definitively established the correct structure of auranthine.
- This work corrects the scientific record regarding auranthine's chemical architecture.
- The findings pave the way for understanding the biosynthesis and potential bioactivity of this fungal benzodiazepine.
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