Several analogues of 7-O- and 4'-O-substituted isoxanthohumol and 8-prenylnaringenin, the strongest known phytoestrogen and potential anticancerogenic agent, were synthesized. Acyl, alkyl, and allyl derivatives of isoxanthohumol underwent the demethylation process using MgI2 x 2Et(2)O in anhydrous THF with the yields of 61-89%. Some of the compounds approached the international criteria of antiproliferative activity (4 mu g/ml) for synthetic agents against the human cancer cell lines.