Synthesis of epothilones

摘要

Commercially feasible methods for synthesizing various epothilones precursors needed for the preparation of final epothilones are provided, including techniques for the synthesis of epothilone segment A and C precursors. Segment C precursors are prepared using starting nitriles, which can alternately be oxidized to ketones and converted, or reacted to form the diol with subsequent conversion to the segment. Segment A precursors are prepared by reacting a starting enone with a chiral catalyst to give an intermediate alcohol in high enantomeric excess, followed by conversion of the alcohol to the desired Segment A precursor.