In order to find more active anti-neuroinflammatory sinomenine derivatives, 17 sinomenine 4-hydroxy esters were designed and prepared. All synthesized derivatives were structurally confirmed by ESI-MS and PMR. Their anti-neuroinflammatory effects were evaluated using LPS-stimulated BV-2 microglia cells. Among them, four compounds presented more than 80% of cell viability. Compound 8 showed remarkable