The occurrence of 5-Hydroxy-7,4'-dimethoxy-6-methylflavone in <i>Eucalyptus</i> waxes

Abstract

5-Hydroxy-7,4'-dimethoxy-6-methylflavone (II) has been shown to occur with 5-hydroxy-7,4'-dimethoxy-6,8-dimethylflavone (I) in the leaf waxes of Eucalyptus torelliana F. Muell. and E. urnigera Hook. The nuclear magnetic resonance spectra of (II) and related compounds have been measured, and it is shown that N.M.R. spectroscopy is useful in determining the relative proportions of the two components at equilibrium in a Wessely-Moser rearrangement. Leaf waxes from several Angophora species also contain compound (I).