Biflavonoids, Quinones and Xanthones as Rare Chemical Markers in the Family Iridaceae

Christine A. Williams and Jeffrey B. Harborne Botany Department, Plant Science Laboratories, University of Reading, Reading, U.K. Z. Naturforsch. 40c, 325 — 330 (1985); received February 4, 1985 Patersonia, Sisyrinchium, Sparaxis, Tigridia, Iridaceae Amentoflavone has been characterised from leaves of Patersonia glabrata. This is the first report of a biflavone in the Monocotyledoneae. The quinone plumbagin, a characteristic con­ stituent of three dicotyledonous families, is now found to be a useful marker for the genus Aristea; it also occurs in two Sisyrinchium species and in Sparaxis tricolor. Mangiferin, a C-glucosylxanthone known previously in the Iridaceae only from Crocus, Iris and Gynandriris has now been found in Eleutherine, Rigidella, Gelasine and Tigridia. results is discussed.