High affinity and selective small molecule agonists of the S1P4 receptor (S1P4-R) may have significant therapeutic utility in diverse disease areas including autoimmune diseases, viral infections and thrombocytopenia. A high-throughput screening (HTS) of the Molecular Libraries-Small Molecule Repository library identified 3-(2-(2, 4-dichlorophenoxy) ethoxy)-6- methyl-2-nitropyridine as a moderately potent and selective S1P4-R hit agonist. Design, ...