Coumarins and related compounds in members of the connaraceae.

Members of the Cnestis, Agelea and Byrsocarpus genera (Connaraceae) examined, viz. C. corniculatus, C. ferruginea, A. nitida, A. obliqua, A. trifolia and B. coccineus, all of which are toxic to rabbits, contained dicoumarol and 4-hydroxycoumarin, the concentration of dicoumarol being relatively low in fresh leaves. Coumarin and a glycoside of coumaric acid were also present in some species. The production of dicoumarol may be due to the presence of a micro-organism, since it was present in higher concentration in mouldy leaves.