Tafluprost ethyl amide is derived from 17-phenyl trinor Prostaglandin F_2α(17-phenyl trinor PGF_2α). A number of 17-phenyl trinor PGF_2α derivatives have been approved for the treatment of glaucoma.^1,2,3,4 Of these, the ones wherein the 13,14-double bond has been hydrogenated retain relatively good potency, but show a significantly reduced incidence of local irritant side effects.⁵ Alternatively, it was recently reported that analogs incorporating a 15-deoxy-15,15-difluoro modification also had a favorable ophthalmic activity profile.⁶ Tafluprost is a 2-series, 16-phenoxy analog of PGF_2α with the 15,15-difluoro substitution. As a free acid, Tafluprost is a very potent FP receptor agonist (K_i = 0.4 nM).⁶ Ethyl amides of PGs tend to increase lipid solubility, to improve uptake into tissues and to further lower the effective concentration.

≥98%