An Ireland-Claisen rearrangement/RCM based approach for the construction of the EF-ring of ciguatoxin 3C

The EF-ring of ciguatoxin 3C, a marine toxin from the dinoflagellate Gambierdiscus toxicus, was stereoselectively synthesized by iterative use of a cyclic ether formation process based on chirality-transferring Ireland-Claisen rearrangement and ring-closing olefin metathesis.