Benzophenones and xanthones with isoprenoid groups from Cudrania cochinchinensis

Four new benzophenones with two isoprenoid groups, cudraphenones A-D (1-4), and three new xanthones also with two isoprenoid units, cudraxanthones P-R (5-7), were isolated from the roots of Cudrania cochinchinensis, together with 19 known phenolic compounds. The structures of the new compounds were elucidated by spectroscopic methods. Some compounds exhibited weak cytotoxi city against human oral squamous carcinoma cells (HSC-8) and normal human g ingival fibroblasts (HGF). Among them, benzophenones 1-4 showed more potent cytotoxic activities against HSC-2 cells than against HGF cells. On the ot her hand, xanthones bearing isoprenoid groups showed much lower tumor speci ficity as compared with the benzophenones, except for geronthxanthone H and isoalvaxanthone. The presence of two sets of hydrophobic and hydrophilic g roups in separate domains in each molecule might play a role in the mediati on of tumor-specific action.