Model studies towards the challenging angularly-oxygenated core of several angucyclinones from an oxidative dearomatization strategy.

Up to six differently substituted highly challenging angularly-oxygenated tricyclic core models of natural angucyclinones were stereoselectively synthesized from a common p-quinol intermediate obtained from Oxone-mediated oxidative dearomatization of the corresponding tricyclic phenol.

Stereoselective synthesis of the C15-C26 fragment of the antitumor agent (-)-dictyostatin.

The synthesis of the C15-C26 fragment of (-)-dictyostatin is reported in 10 steps and 28% overall yield. The key steps are the two stereoselective sulfoxide-directed processes: a Reformatsky-type reaction and a ß-keto sulfoxide reduction.