(3aR,??4R,??5R,??6aS)??-??4-??((E)??-??3,??3-??Difluoro-??4-??phenoxybut-??1-??en-??1-??yl)??-??2-??oxohexahydro-??2H-??cyclopenta[b]??furan-??5-??yl Benzoate is an intermediate in the synthesis of Tafluprost (T004820), a novel prostanoid used in the treatment of glaucoma and is the first prostanoid to be released in a preservative free-formula.