Bioinspired Synthesis of Alstoscholarinoids A and B
Nicolas Kratena1, Maximilian Kaiser1, Kirill Naumov1
1Institute of Applied Synthetic Chemistry, TU Wien, Getreidemarkt 9, A-1060 Vienna, Austria.
JACS Au
|March 28, 2025
Summary
Researchers developed a biomimetic synthesis for Alstoscholarinoids A and B, complex triterpenes from the Alstonia scholaris tree. This efficient synthesis revises the proposed biosynthetic pathway for Alstoscholarinoid A.
Area of Science:
- Natural Product Synthesis
- Organic Chemistry
- Biomimetic Chemistry
Background:
- Alstonia scholaris tree yields complex rearranged triterpenes like Alstoscholarinoids A and B.
- Biomimetic synthesis offers an efficient route to complex natural products by mimicking biosynthetic pathways.
- Cascade reactions are key to addressing challenging structural features in natural product synthesis.
Purpose of the Study:
- To achieve a short and efficient biomimetic synthesis of Alstoscholarinoids A and B.
- To investigate and revise the proposed biosynthetic origin of Alstoscholarinoid A.
- To explore proposed intermediates in the biosynthesis of these compounds.
Main Methods:
- Utilized cascade reactions, including a Schenck-Ene reaction, Hock rearrangement, and aldol addition.
- Employed a transannular aldol addition to construct key structural features.
- Developed a bioinspired synthetic strategy based on biosynthetic hypotheses.
Main Results:
- Successfully synthesized Alstoscholarinoids A and B in a short and efficient manner.
- The synthetic route led to a revision of the likely biosynthetic origin of Alstoscholarinoid A.
- Key synthetic steps included a transannular aldol addition and a multi-step cascade reaction.
Conclusions:
- The biomimetic synthesis provides a viable and efficient route to Alstoscholarinoids A and B.
- The study offers new insights into the biosynthesis of Alstonia scholaris triterpenes.
- This work highlights the power of synthesis in revising proposed natural product structures and pathways.
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