Synthesis and antiproliferative activities of novel 5'-Schiff-base group substituted psoralen derivatives

It was found that psoralen derivative could perform a Friedel-Crafts acylation smoothly with acetic anhydride to give 5'-acetylpsoralen in a 73% yield.  In the presence of boron trifluoride etherate, 5'- acetylpsoralen reacted with both aromatic amines and aliphatic amine smoothly to afford 5'-Schiff-base group substituted psoralen derivatives in 72%-92% yields.  The novel synthetic method has the advantages of cheap materials, mild reaction conditions, good yields and high regioselectivity in the Friedel-Crafts acylation.  Cell viability assay by MTT demonstrates that some of the psoralen derivatives 6 have antiproliferative activities.