To discover novel peroxisome proliferator-activated receptor γ (PPARγ) agonists that could be used as antidiabetic agents, we designed docosahexaenoic acid (DHA) derivatives (2 and 3), which have a hydrophilic substituent at the C (4)-position, based on the crystal structure of the ligand-binding pocket of PPARγ. These compounds were synthesized via iodolactone as a key intermediate. We found that both DHA derivatives (2 and 3) showed ...