Alpha-pyrone compositions and method for the chemoprevention of cancer

A method of chemopreventing cancer by administering to a mammal a cancer chemopreventive composition of matter, comprising an effective amount of at least one alpha-pyrone compound having the following structural formula:

• 4
• in which R1 is a hydrogen atom or an alkoxy radical having 1 to 4 carbon atoms, R2 is a hydrogen atom or a hydroxyl group, and R3 is an alkyl radical having from 1 to 4 carbon atoms or a styryl or phenethyl radical optionally substituted by one or two methylenedioxy radicals or one or two hydroxyl groups and/or one or two alkoxy radicals having from 1 to 4 carbon atoms, with the proviso that, when R2 is a hydroxyl group, then R3 is necessarily an unsubstituted phenethyl radical, with the proviso that when R3 is an alkyl radical having 1 to 4 carbon atoms, then R1 and R2 cannot both be hydrogen, in a physiologically acceptable carrier medium for the purpose of preventing cancer sensitive to the formula.