Nice contribution in total synthesis from Laurent Commeiras and Edouard Fauran at iSm2 - institut des Sciences Moléculaires de Marseille and Jean-Valère Naubron at FSCM.
Pandanus amaryllifolius produces unusual alkaloids (pandanusines A and B and pandamarine) featuring rare diazaspirocyclic γ-lactam frameworks.
The team reports concise total syntheses of all three, based on a modular copper(I)-catalyzed reaction. γ-Hydroxy-γ-lactams, built from iodoacrylic acids, terminal alkynes, and primary amines, are converted via N-acyliminium ions into the diazaspirocyclic core.
✅ (±)-Pandanusine B: 4 steps, 40% overall yield
✅ (±)-Pandanusine A: 5 steps, 26.5% overall yield
✅ Extension to the more complex pandamarine
The absolute configurations of the pandanusine A and B enantiomers were also assigned using VCD/ECD and DFT/TD-DFT calculations.
Congratulations to Edouard and all co-authors! 🙏
📄 Full paper: https://lnkd.in/ehY6WQ3q
#TotalSynthesis #OrganicChemistry #NaturalProducts #Alkaloids #Catalysis
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