Disclosed are: a compound which has excellent metabolic stability and selectively binds to EP4 receptor； and a pharmaceutical product which contains the compound.Specifically disclosed is a compound represented by formula (1) (wherein R and R each independently represents a hydrogen atom or a linear alkyl group having 1-3 carbon atoms, and R represents a hydrogen atom, an alkyl group having 1-4 carbon atoms, an alkoxyalkyl group, an aryl group, a halogen atom or a halogenated alkyl group) or a pharmaceutically acceptable salt thereof, which is different from publicly known PGIs and has a selective EP4 agonist action. Consequently, a pharmaceutical product which contains the compound is useful for prophylaxis and/or treatment of immune diseases, cardiovascular diseases, heart diseases, respiratory diseases, eye diseases, kidney diseases, hepatic diseases, bone diseases, digestive tract diseases, neurological diseases, skin diseases and the like.
