The uropygiols: identification of the unsaponifiable constituent of a diester wax from chicken preen glands.

The chief lipid fraction in the uropygial gland excretion of the domestic hen is a diester wax. The saponifiable fraction of this wax consists of saturated normal C(10)-C(20) fatty acids. The unsaponifiable fraction consists of a series of three homologous compounds, which have been named the uropygiols and identified by mass spectrometry, gas-liquid chromatography, and periodate cleavage as 2,3-n-alkanediols containing 22-24 carbon atoms. The native diols were shown to consist of about equal amounts of the threo and erythro isomers. Records of analyses of the natural products as well as related synthetic compounds are shown.