Imperatorin is a furocoumarin and a phytochemical that has been isolated from Urena lobata L. (Malvaceae), Angelica archangelica,[1] Angelica dahurica,[2] Glehnia littoralis,[3] Saposhnikovia divaricata,[4] Cnidium monnieri,[5] Incarvillea younghusbandii,[6] and Zanthoxylum americanum mill.

[8] The procedure for the isolation of imperatorin from Urena lobata involves exhaustively extracting under reflux with benzene the air-dried and pulverised roots followed by separation by column chromatography.

[9] Imperatorin was identified from a Bioactive Molecules library in a high throughput screening experiment for inhibitors of the phosphodiesterase PDE4.

[10] Imperatorin has been shown to have anti-inflammatory activity in chondrocytes.

[11] Imperatorin treatment inhibits the expression of iNOS and suppresses the production of NO in osteoarthritic chondrocytes.