Discovery of 2-(((1r,4r)-4-(((4-Chlorophenyl)(phenyl)carbamoyl)oxy)methyl)cyclohexyl)methoxy)acetate(Ralinepag): An Orally Active Prostacyclin Receptor Agonist for theTreatment of Pulmonary Arterial Hypertension. Here, PTGIR is linked to pulmonary arterial hypertension.