17-phenyl trinor PGE2 is a synthetic analog of PGE2. It is an EP1 and EP3 receptor agonist. 17-phenyl trinor PGE2 is an EP1 and EP3 receptor agonist. It causes contraction of the guinea pig ileum at a concentration of 11 µM. It is slightly less potent than PGE2 in stimulating gerbil colon and rat uterus. With an ED50 value of 350 µg/kg, 17-phenyl trinor PGE2 is 4.4 times more potent than PGE2 as an antifertility agent in hamsters.