Versatile Oxabicyclic Synthons: Studies on C8-Oxygenated Eunicellin Diterpenes

Phillip M. Pelphrey; David B. Bolstad; Dennis L. Wright

doi:10.1055/s-2007-986667

LETTER

Versatile Oxabicyclic Synthons: Studies on C8-Oxygenated Eunicellin Diterpenes

Phillip M. Pelphrey^c, David B. Bolstad^a, Dennis L. Wright*^a,b
^a Department of Pharmaceutical Sciences, University of Connecticut, Storrs, CT 06269-3092, USA
Fax: +1(860)4865792; e-Mail: dennis.wright@uconn.edu;
^b Department of Chemistry, University of Connecticut, Storrs, CT 06269-3060, USA
^c Department of Chemistry, Dartmouth College, Hanover, NH 03755, USA

Abstract

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Abstract

In this letter, we describe the first approach to the synthesis of C8-oxygenated eunicellin diterpenes starting with a highly functionalized 8-oxabicyclo[3.2.1]octadiene system. The route features two sequential annulations to append a six- and five-membered ring onto the core structure followed by oxidative cleavage to reveal the eunicellin skeleton. Key to this strategy is a diastereoselective intramolecular Nozaki-Hiyama-Kishi (NHK) closure to establish the correct relative stereochemical relationship at C6 and C8 of the natural product.

Key words

natural products - furans - ring closure - cycloadditions - cyclopropenes

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References

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