Asymmetric Total Syntheses of Cochliomycin A and Zeaenol

The first asymmetric total syntheses of two resorcylic acid lactones (RALs) cochliomycin A and zeaenol have been achieved in a divergent way. The main highlight of our strategy involves successful application of stereoselecive Keck allylation and JuliaKocienski olefination to access an advanced intermediate, by starting from L-tartaric acid as a chiral pool compound. This intermediate is coupled with a trisubstituted benzoic acid to afford a common RCM precursor for both target molecules. Ring-closing metathesis at a late stage, followed by functional group manipulation, yielded the target molecules in an efficient way.