Application of the Anionic Oxy-Cope Rearrangement to Stereocontrolled Synthesis of the A/B Subunit of Cytoxic 8,9-Seco-ent-kaurenes

Gaétan Ladouceur; Leo A. Paquette

doi:10.1055/s-1992-34185

Synthesis 1992; 1992(1/2): 185-191
DOI: 10.1055/s-1992-34185

paper

© Georg Thieme Verlag, Rüdigerstr. 14, 70469 Stuttgart, Germany. All rights reserved. This journal, including all individual contributions and illustrations published therein, is legally protected by copyright for the duration of the copyright period. Any use, exploitation or commercialization outside the narrow limits set by copyright legislation, without the publisher's consent, is illegal and liable to criminal prosecution. This applies in particular to photostat reproduction, copying, cyclostyling, mimeographing or duplication of any kind, translating, preparation of microfilms, and electronic data processing and storage.

Application of the Anionic Oxy-Cope Rearrangement to Stereocontrolled Synthesis of the A/B Subunit of Cytoxic 8,9-Seco-ent-kaurenes

Gaétan Ladouceur^* , Leo A. Paquette

^*Evans Chemical Laboratories, The Ohio State University, Columbus, Ohio 43210, USA

Abstract

PDF Download All articles of this category

Methodology is described for expedient synthesis of the A/B framework of 8,9-seco-ent-kaurenes and for introduction of the 5-methylene-2-cyclopentenone moiety. In the first part of the study, a sequence of only six steps is necessary to convert 2-(hydroxymethylene) cyclohexanone to a key functionalized intermediate. Five of the transformations are 100% stereocontrolled as a direct result of complementary steric biases that operate in the desired direction. The final target is arrived at by selective protection/oxidation of the oxygenated centers. This first synthetic entry to the structural core of the titled diterpenes is expected to guide the future de novo acquisition of these cytotoxic agents.

PDF (574 kb)