Iriomoteolides are novel macrolides possessing either a unique 15-membered or a 20-membered macrocycle, and displaying
exceedingly potent cytotoxicity with IC50 values of up to 2 ng/mL. Thus far, over a period of about four years, ten research groups
worldwide have published their synthetic efforts resulting in four total syntheses of iriomoteolides and a few diastereomers thereof, and a
number of fragment and macrocyclic core syntheses. Interestingly, three total syntheses involved ring-closing metathesis as the key step
for the construction of the macrocycle, whereas the synthesis of three fragments was accomplished using a cross-metathesis reaction.
Herein we highlight assets and limitations of the olefin metathesis reaction in the synthesis of the title compounds.