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A Strategy for Sensitive, Large Scale Quantitative Metabolomics
Published on: May 27, 2014
Total synthesis of brasoside and littoralisone
Ian K Mangion1, David W C MacMillan
1Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, USA.
Abstract:
The first total syntheses of littoralisone (1) and brasoside (2) have been achieved in 13 overall steps. Both natural products are forged from a common intermediate which is rapidly assembled using organocatalytic technology, including a proline-catalyzed alpha-aminoxylation and a contra-thermodynamic intramolecular Michael addition. Application of the two-step carbohydrate synthesis technology has enabled to access a selectively substituted glucose derivative for use as an intramolecular cycloaddition tether. This synthesis culminates with an intramolecular [2+2] photocycloaddition that serves to support the proposed biosynthetic origins of 1 from 2.
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