Stereoselective Formation of a β-Lactam Fused Oxathiazepin: A Synthetic Approach to Eudistomins

Abstract

A synthetic approach to eudistomin via a β-lactam fused bicyclic oxathiazepin intermediate is described. A β-lactam fused oxathiazepin derivative was synthesized by intramolecular 7-membered oxime ether formation and subsequent face-selective reduction of the C-N double bond. A fully functionalized ortho-alkenylphenylthioanilide bearing oxathiazepin ring was then prepared and construction of the indole skeleton under several radical-mediated conditions was examined.

eudistomin - bicyclic β-lactam - oxathiazepin - 2,3-di­substituted indole - radical cyclization

References

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Figure 2 Structures of 17, 25, and 26

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