With the goal of discovering a selective agonist of estrogen-related receptor gamma (ERRgamma) with enhanced potency, we designed a series of small-molecule ligands derived from a known ERRgamma agonist, GSK4716, that can substantially potentiate the transcriptional activity of ERRgamma. Individual compounds among a 30-member library of acyl hydrazones were pre-evaluated through in silico docking studies on the receptor cavities of ERRgamma LBDs using X-ray crystal structures cocrystallized with GSK4716 and 4-OHT. This rational approach to achieve the enhanced potency in ERRgamma transcriptional activity with selectivity over ERRalpha/beta enables us to complete the construction of a focused library by carrying out microwave-assisted parallel synthesis with excellent yields and purities. Finally, we identified a more potent ERRgamma agonist, E6, with excellent selectivity over ERRalpha/beta.