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Updated: Jul 5, 2026

Preparation of Stable Bicyclic Aziridinium Ions and Their Ring-Opening for the Synthesis of Azaheterocycles
Published on: August 22, 2018
Total synthesis of (+)-amphidinolide A. Structure elucidation and completion of the synthesis
Barry M Trost1, Paul E Harrington, John D Chisholm
1Department of Chemistry, Stanford University, Stanford, California 94305-5080, USA. bmtrost@stanford.edu
Abstract:
The structure elucidation of (+)-amphidinolide A, a cytotoxic macrolide, has been accomplished by employing a combination of NMR chemical shift analysis and total synthesis. The 20-membered ring of amphidinolide A was formed by a ruthenium-catalyzed alkene-alkyne coupling to forge the C15-C16 bond. Using the reported structure 1 as a starting point, a number of diastereomers of amphidinolide A were prepared. Deviations of the chemical shift of key protons in each isomer relative to the natural material were used as a guide to determine the locations of the errors in the relative stereochemistry. The spectroscopic data for the synthetic and natural material are in excellent agreement.
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