Fig. 2. Predicted binding poses of docking hits and their structure-based optimization.
a, b Docked poses of 66 and 71, respectively. c Docked pose of 74. Dotted lines indicate hydrogen bonds. Note that while the carboxylate of 71 is out of hydrogen-bond range of Arg316, the two groups maintain an ionic interaction, contributing to the overall positive electrostatic potential in this region. d Structure-based optimization of 71. e Concentration-response curves of compounds shown in d) using BRET-based EP4R-arrestin interaction reporter assay. f Calculated Ki values (using the Cheng-Prusoff approximation) of compounds shown in d). Data in e) represents mean ± SEM of three independent experiments. Source data are provided as a Source Data file.