Synthesis and assignment of absolute configuration of the iridoid 9-deoxygelsemide.

  title={Synthesis and assignment of absolute configuration of the iridoid 9-deoxygelsemide.},
  author={Alessandro D'alfonso and Maurizio Pasi and Alessio Porta and Giuseppe Zanoni and Giovanni Vidari},
  journal={Organic letters},
  volume={12 3},
The first enantioselective synthesis of 9-deoxygelsemide, belonging to a rare group of iridoids isolated from Gelsemium plants, is described. The key synthetic steps are a variant of the Woodward-Prevost reaction to install the characteristic cis-alpha-1,2-dioxygenated system at C-6 and C-7 with complete diastereoselectivity. Construction of the dihydropyran ring was achieved via formylation of lactone I, followed by dehydration of the corresponding lactol. The synthesis allowed assignment of… Expand
9 Citations
A Formal Synthesis of Iridoid 9-Deoxygelsemide
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The synthetic strategy features a diastereoselective intramolecular Pauson-Khand reaction (IPKR) to construct the iridoid framework followed by some strategic synthetic manipulations to access the targeted monoterpenes including those having diverse oxy-functionalization patterns and with 3-5 contiguous stereogenic centres in a highly stereocontrolled manner. Expand
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Total synthesis of gelsemiol.
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Olefination, Metathesis, and Epoxidation Reactions
  • Applied Organic Chemistry
  • 2020