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Updated: Aug 21, 2026

Preparation of Stable Bicyclic Aziridinium Ions and Their Ring-Opening for the Synthesis of Azaheterocycles
Published on: August 22, 2018
Synthesis of the azaspiracid-1 trioxadispiroketal
Lisa K Geisler1, Son Nguyen, Craig J Forsyth
1Department of Chemistry, Institute of Technology, University of Minnesota, 207 Pleasant Street S.E., Minneapolis, Minnesota 55113, USA.
Abstract:
The de novo analysis, design, and synthesis of the azaspiracid-1 trioxadispiroketal system is described. A revised structural model was developed on the basis of an independent analysis of the NMR spectral data of the natural product that fit all of the data and the thermodynamically favored spiroketal paradigm. This model was then tested via synthesis using a novel trioxadispiroketalization process and supported by spectroscopic correlation.
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