Kudzuisoflavone-A was successfully synthesised via oxidativedimerisation of daidzein in the presence of cuprous chloride. Appropriately substituted isoflavones also undergo regioselective oxidativedimerisation when treated with thallium trifluoroacetate to give novel 6′,6′″-biisoflavones in good yield. A rationale for the regioselectivity is proposed.