Biogenetic-type transformation of 3-keto-4,5-epoxy-eudesmanes: synthesis of cyperanes, eremophilanes and spirovetivanes

✍ Scribed by P. Ceccherelli; M. Curini; M.C. Marcotullio; O. Rosati

• Publisher: Elsevier Science
• Year: 1989
• Tongue: French
• Weight: 523 KB
• Volume: 45
• Category: Article
• ISSN: 0040-4020
• DOI: 10.1016/s0040-4020(01)89241-3

✦ Synopsis

Cyperanes, eremophilanes and spirovetivanes have been prepared by acid catalyzed rearrangement of 3-keto-4,5-epoxy-eudesmanes. These transformations are of biogenetic significance and reinforce the hypothesis that the oxigenate eudeemanes are precursors of several sesquiterpene skeletons. Recently we have reported the isolation from aerial parts ofDittrichia viscosa of a new sesquiterpene, the cyperanic acid, which was identified as la on the basis of chemical transformations and spectroscopical data. 1 This compound is representative of a small group of natural products which incorporate the cyperane framework and possess a carbonyl function at C4 , e.g. la, Z2, 33 and 4 4,5 . la R=H lb R=Me