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Efficient formal synthesis of (+/-)-hyphodermin B.

Luke C Henderson·Wendy A Loughlin·Ian D Jenkins·Peter C Healy·Marc R Campitelli
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Abstract

An efficient formal synthesis of hyphodermin B 1, a metabolite of Hyphoderma radula, has been completed in 15% overall yield. The tricyclic carbon skeleton 3 was rapidly assembled from a novel vinyl enone via a Diels-Alder reaction, followed by dehydrogenation and anhydride formation. Selective reduction of anhydride 3 with LiAlH(t-BuO)3 gave hyphodermin B 1 in 99% yield. The structure of hyphodermin B 1 was confirmed by X-ray crystallographic analysis. The anhydride 3, bearing a gamma-carbonyl group, displayed unexpected reactivity with the anhydride carbonyl closest to the gamma-ketone being the most electrophilic site. This was confirmed by HF/6-31G calculations. In the presence of base, 3 underwent a rearrangement to the novel lactone 16.

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Crystallography, X-RayFuransKetonesModels, MolecularMolecular StructureNaphthalenesPolyporalesStereoisomerismJournal ArticleResearch Support, Non-U.S. Gov't

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Luke C Henderson, Wendy A Loughlin, Ian D Jenkins, Peter C Healy, Marc R Campitelli. 2006-03-17. Efficient formal synthesis of (+/-)-hyphodermin B.. https://doi.org/10.1021/jo052485l

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