The selective and efficient oxidation of flavanones with dimethyldioxirane
(DMD) is reported. Aromatic rings carrying methoxy groups were selectively
hydroxylated in neutral and acidic media. In the latter case inversion of c
hemoselectivity with respect to the benzylethereal position was observed. T
his behaviour was exploited to obtain polyhydroxylated flavanones, which ar
e compounds with potential antioxidant and biological properties. (C) 2000
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