Saikogenin D is isolated from?Bupleurum chinense, has anti-inflammatory effects. Saikogenin D activates epoxygenases that converts arachidonic acid to epoxyeicosanoids and dihydroxyeicosatrienoic acids, and the metabolites secondarily inhibit prostaglandin E2 (PGE2) production. Saikogenin D results in an elevation of [Ca2+]i due to Ca2+ release from intracellular stores.

EP4 receptor antagonist 1 inhibits human and mouse EP4 receptor with IC50s of 6.1 nM and 16.2 nM, respectively.

MF-766 is a highly potent, selective and orally active EP4 antagonist with a Ki of 0.23 nM. It behaves as a full antagonist with an IC50 of 1.4 nM (shifted to 1.8 nM in the presence of 10% HS) in the functional assay. It can be used for cancer and inflammation diseases research.