The sphingosine-1-phosphate-1 (S1P<sub>1</sub>) receptor agonists have great potential for the treatment of multiple sclerosis (MS) because they can inhibit lymphocyte egress through receptor internalization. We designed and synthesized triazole and isoxazoline derivatives to discover a novel S1P<sub>1</sub> agonist for MS treatment. Of the two scaffolds, the isoxazoline derivative was determined to have excellent <i>in vitro</i> efficacy and drug-like properties. Among them, compound <b>21l</b> was found to have superior drug-like properties as well as excellent <i>in vitro</i> efficacies (EC<sub>50</sub> = 7.03 nM in β-arrestin recruitment and EC<sub>50</sub> = 11.8 nM in internalization). We also confirmed that <b>21l</b> effectively inhibited lymphocyte egress in the peripheral lymphocyte count test and significantly improved the clinical score in the experimental autoimmune encephalitis MS mouse model.