Many Eucalyptus waxes contain as major
components long-chain β-diketones, which may be readily separated from the
rest of the wax as insoluble copper complexes. The most commonly occurring β-diketone
is n-tritriacontan-16,18-dione, but in two species, Eucalyptus risdoni and E.
coccifera, β-diketones of shorter chain length predominate. From the waxes
of several Eucalyptus species a new flavone, 5-hydroxy-
4',7-dimethoxy-6,8-dimethylflavone, and a new triterpene, 11,l2-dehydroursolic
lactone acetate, have been isolated.
Gas chromatography has been used to
determine the chain length distribution of β-diketones, hydrocarbons, and
esters from several waxes. The esterified alcohols of Eucalyptus globulus and
E. risdoni belong to two series-long-chain n-alkan-1-ols of predominantly even
carbon number, and n-alkan-2-ols of medium chain length and predominantly
uneven carbon number (n-C9, n-C11, n-C13, and
n-C15).
Impacts of cross-linker chain length on the physical properties of polyampholyte hydrogels
