APJ receptor agonist 1, a potent biphenyl acid derivative, acts as an agonist (EC50 of 0.093 nM and 0.12 nM for human and rat APJ receptors, respectively) for the APJ receptor (APJ-R). It exhibits significant in vitro potency towards apelin-13, the endogenous peptidic ligand for the APJ receptor. APJ receptor agonist 1 holds promise for heart failure research.

The S-atropisomer of APJ receptor agonist 1 (compound 15a) exhibits 200 times greater potency than its R-atropisomer counterpart.[1].

APJ receptor agonist 1, administered via intravenous infusion at dosages of 10-100 μg/min/kg, resulted in a 10% enhancement of cardiac output (CO) with negligible effects on blood pressure, specifically less than a 5% transient reduction. This outcome was observed in isoflurane-anesthetized male Sprague Dawley rats. The administration involved infusing the compound into the jugular vein for 15 minutes, demonstrating a dose-dependent increase in cardiac output without significant alterations in mean arterial blood pressure or heart rate[1].