A novel furocoumarin derivative named oxyalloimperatorin (1), together with seventeen furocoumarins 2-18 were isolated from the radix of Angelica dahurica. The chemical structure of new metabolite was characterized by analysis of IR, NMR, and HR-ESI-MS spectroscopic data. Among the isolated compounds, 13, 16, and 18 (each at 20 mu M) could significantly promote the gene transcriptional function of nuclear receptor RXR alpha. While 7-9, 13, 14, and the new structure 1 (each at 20 mu M) showed significant reduction in RXR alpha gene transcriptional activities induced by 9-cis-retinoid acid. The findings indicated that these furocoumarin skeleton derivatives might hold beneficial effects on many intractable diseases, such as cancer and metabolic diseases, due to their potential activities on regulating the transcriptional activation function of RXR alpha. ; Xiamen Science and Technology Key program [3502Z20100006]; Fujian major program [2009Y3004]; Fundamental Research Funds for the Central Universities [20101211000]; National Natural Science Foundation of China (NSFC) [30873146]