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Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
Published on: July 17, 2020
Synthesis of the bis-tetrahydropyran core of amphidinol 3
Michael T Crimmins1, Timothy J Martin, Theodore A Martinot
1Kenan and Caudill Laboratories of Chemistry, University of North Carolina at Chapel Hill, North Carolina 27599, USA. crimmins@email.unc.edu
Abstract:
A convergent synthesis of the C31-C52 bis-tetrahydropyran core of the natural product amphidinol 3 is reported. A common intermediate was synthesized from d-tartaric acid utilizing an asymmetric glycolate alkylation/ring-closing metathesis sequence to construct the THP rings. Differential elaboration of the common intermediate allowed the synthesis of two distinct coupling partners which were joined through a modified Horner-Wadsworth-Emmons olefination to provide the bis-tetrahydropyran core.
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