Short and Stereoselective Total Synthesis of $Δ$-11,13-Didehydroguaianes and -guaianolides: Synthesis of (±)-Achalensolide and (±)-Pechueloic Acid; Revision of the Structure of (+)-Rupestonic Acid.
(±)-Pechueloic acid (I), (±)-rupestonic acid (7-epi-pechueloic acid), and (±)-achalensolide (II) (guaian-8-12-olide class) were prepd. stereoselectively in only nine steps from the com. available tropylium cation via central intermediate 6, which is used as a general and efficient precursor to bicyclo[5.3.0]decane sesquiterpenes. The method does not require function protection. It is highly regio- and stereoselective thanks to an efficient C-1 epimerization, a selective C-8,9 hydrogenation, and a stereocontrolled 1,6-conjugate addn. of an acrylate equiv. These $Δ$-11,13-didehydroguaianes and-guaianolides are good Michael acceptors and hence biol. active. (© Wiley-VCH Verlag GmbH {&} Co. KGaA, 69451 Weinheim, Germany, 2009). [on SciFinder(R)]
Références
- Titre
- Short and Stereoselective Total Synthesis of $Δ$-11,13-Didehydroguaianes and -guaianolides: Synthesis of (±)-Achalensolide and (±)-Pechueloic Acid; Revision of the Structure of (+)-Rupestonic Acid.
- Type de publication
- Article de revue
- Année de publication
- 2009
- Revue
- European J. Org. Chem.
- Pagination
- 3678–3682, S3678/1–S3678/22
- ISSN
- 1434-193X
Soumis le 12 avril 2018