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HISPIDULIN (60methoxy-5,7,4’-trihydroxyflavone) known for its cytotoxic properties,’ was first identified from the leaf extract of Ambrosia hispida,2 and was later detected in a number of other Compositae species: Iva nevadensi,q3 and I. hayesiana,4 I. fiutescens,’ Ambrosia ambrosioide$j Gaillardia fastigiata, 7 Eupatorium cune$oliuml and E. rotundifolium,l Flourensia cernua,8 Hymenoxys odoratag and H. richardsonii var. JEoribundag and Helenium autumnale?O As the result of several separate biochemical systematic investigations of still other genera in the Compositae, we can now report the occurrence of hispidulin in 34 additional species of Ambrosia, Gaillardia, Helenium, Hymenoxys, Plummera and Ratibida (Table 1). It is of particular interest to note that, with the exception of the Eupatorium species, all of the Compositae genera in which hispidulin has been found are recognized as members of two closely related tribes, the Helenieae and Heliantheae. Although hispidulin appears to be widespread in these two tribes, it is not restricted to the Compositae; it has also been reported from the Scrophulariaceae (Digitalis lanata) l1 and the Pedaliaceae (Pedalium |
