Syntheses of retipolide E and ornatipolide, 14-membered biaryl-ether macrolactones from mushrooms

Publikation: Beiträge in ZeitschriftenZeitschriftenaufsätzeForschung


Two approaches for the total synthesis of the spiromacrolide retipolide E (5) are described, the first using a modified Mitsunobu reaction as key step for the formation of the strained 14-membered macrolactone, the second a nucleophilic aromatic substitution (S NAr). In the first approach an α-oxomacrolactone 15 was obtained, which could either be converted into ornatipolide (6) or further transformed into racemic retipolide E [(R,S)-5] by directed aldol condensation with a methyl arylpyruvate. The second approach allowed the synthesis of either racemic or enantiomerically pure retipolide E (5). In the latter case Evans' methodology was used for the introduction of stereogenic center via stereoselective alkylation. The oxazolidinone auxiliary was removed under mild conditions by exchange for 2-arylethanol 22 with Otera's distannoxane catalyst. Synthetic retipolide E allowed the identification of this biosynthetic intermediate in the fruit bodies of the North American mushroom Retiboletus retipes.

Seiten (von - bis)6548-6557
Anzahl der Seiten10
PublikationsstatusErschienen - 09.07.2007

Bibliographische Notiz

Funding Information:
We thank the Fonds der Chemischen Industrie for financial support and Prof. H. Shibata, Shinshu University, for kindly comparing compound 6 with authentic ornatipolide. We also thank Dr. Bert Steffan for high field NMR spectra and Drs. Richard Allen and Jörg-Dieter Klamann for linguistic improvements.