Stereoselektive Synthesen von Taxan‐Derivaten

Abstract

Stereoselective Synthesis of Taxane Derivatives Substituted racemic 4,8,12‐trinortaxanes were prepared stereoselectively in several steps from the dienone 10 . A variant of the de Mayo reaction with bicyclononenones 4 and cyclohexen produced the desired configuration at C(8) of the taxane framework. Retro ‐aldol cleavage of the tetracycle 5 led to the taxane skeleton 6 . Stereoselective reduction followed by treatment with base afforded 7b . Hydrolysis of the acetal group and further reduction yielded 9 in which the relative configuration corresponds to the one of the natural products.