Catalytic asymmetric formal synthesis of beraprost

نویسندگان

  • Yusuke Kobayashi
  • Ryuta Kuramoto
  • Yoshiji Takemoto
چکیده

The first catalytic asymmetric synthesis of the key intermediate for beraprost has been achieved through an enantioselective intramolecular oxa-Michael reaction of an α,β-unsaturated amide mediated by a newly developed benzothiadiazine catalyst. The Weinreb amide moiety and bromo substituent of the Michael adduct were utilized for the C-C bond formations to construct the scaffold. All four contiguous stereocenters of the tricyclic core were controlled via Rh-catalyzed stereoselective C-H insertion and the subsequent reduction from the convex face.

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عنوان ژورنال:

دوره 11  شماره 

صفحات  -

تاریخ انتشار 2015