Bioactive metathesis catalysts

Similarly, the 18-membered macrocycle 14, which served as a precursor for the synthesis of a bioactive analog of the anticancer agent antimycin Aj, was quickly produced by domino self-metathesis/RCM from the threonine derivative 13 (Scheme 2.4) [5b]. The Zhan catalyst 5 was shown to be more effective for this key step than the Grubbs catalysts 1 or 2. 

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