Weihe Zhang - Total Synthesis of Absinthin

Version 1

      Publication Details (including relevant citation   information):

      In summary, (+)-absinthin (1) was efficiently constructed in nine

      steps and in 18.6% overall yield from O-acetylisophotosantonic

      lactone,8 a known intermediate available in one step from   santonin.9

      The present synthesis features Mitsunobu arylselenylation,   oxidative

      elimination of allylic arylselenides, a biomimetic dimerization   via

      regio- and stereospecific Diels-Alder reaction, and a four-step

      stereochemical inversion of the highly sterically congested   tertiary

      alcohol. Completion of this synthesis has not only tackled the   formidable

      synthetic challenges in assembling structurally complex

      (+)-absinthin but also paved an efficient synthetic route to a   series

      of medicinally attractive absinthin analogues.

      Abstract:

      (+)-Absinthin, a structurally   unique triterpene, has been efficiently constructed in nine   reaction steps and in 18.6% overall yield from   O-acetylisophotosantonic lactone. The synthesis features   Mitsunobu arylselenylation, oxidative elimination of allylic   arylselenides, biomimetic dimerization via regio- and   stereospecific Diels−Alder reaction, and a four-step   stereochemical inversion of a highly sterically congested   tertiary alcohol. This approach has not only tackled the   formidable synthetic challenges in assembling structurally   complex (+)-absinthin but also   paved an efficient synthetic route to a series of medicinally   attractive absinthin analogues.

      Address (URL): http://pubs.acs.org/doi/abs/10.1021/ja0439219?prevSearch=absinthin&searchHistory Key=