The stereoselective synthesis of methyl monate C 2 is described using as a key step an ene-intramolecular modified Sakurai cyclization (IMSC) reaction to prepare tetrahydropyran 5. An asymmetric allylic alkylation, followed by a cross-metathesis, enables the insertion of the right-hand side chain.
Collective Synthesis of Highly Oxygenated (Furano)germacranolides Derived from Elephantopus mollis and Elephantopus tomentosus
作者:Rémi Patouret、Ning Cham、Shunsuke Chiba
DOI:10.1002/anie.202402050
日期:2024.5.6
The collective synthesis of six (furano)germacranolides derived from Elephantopus mollis and Elephantopus tomentosus was achieved. The assembly of the highly oxygenated ten-membered ring of molephantin and tomenphantopin F was enabled by diastereoselective Barbier allylation coupled with Nozaki–Hiyama–Kishi macrocyclization. The photoinduced cycloisomerization of molephantin enabled access to four