(R)-DPN
(R)-DPN (compound 3) is a selective ERβ ligand with EC50s of 2.9, 0.8 nM for ERα and ERβ, respectively. (R)-DPN shows a very high affinity and potency preference for ERβ over ERα. (R)-DPN shows cytoxicity for HEC-1 and U2OS cells with EC50s of 286, 205 nM, respectively.