We report a new route to F2t-IsoP (formerly named 8-epi-PGF2α) using a biomimetic radicalcyclization of a highly functionalized C20 precursor. The strategy employed gives a β-hydroxy freeradical followed by molecular oxygen trapping, which is an unusual method for quenching carbonfree radicals. We observed the formation of unique diastereoisomers (15R)- and (15S)-F2t-IsoP. Thisresult is consistent with a strong stereoelectronic control associated with a steric effect initiatedby the side chains α and ω on the cyclopentane ring.