abstract |
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 C using a stereoselective Noyori-type reduction, and the coupling of epothilone segments B and C using an aldol condensation reaction. The synthesis methods may be used to prepare naturally occurring segments as well as a large number of related analogs and homologs thereof. Final epothilones in accordance with the invention may also be of the naturally occurring variety (16-membered macrolides), while the homologs and analogs thereof are preferably up to 20-membered macrolides. |