Genus Dorstenia 7,8- from

Fig. (9). Monoprenylated flavones (100-111) of genus Dorstenia with their isomers from other...

A range of simple as well as complex prenylated and geranylated flavonoid derivatives has been isolated and characterized from a number of Dorstenia species. It is interesting to note that all the flavonoids so far reported from this genus appear to be only from African Dorstenia species but more data would have to be obtained to confirm, if indeed this is truly so and if this observation has any chemotaxonomic significance. Monochalcones as well as bichalcones are reported from this genus. 

From the biosynthetic relationship among different classes of flavonoids, flavanones derived from the cyclization of chalcones. Although there is a quite number of biflavanones in the literature, no biflavanone has so far been identified from the Dorstenia genus. 

The distribution of furanocoumarins in the Moraceae raises an important point. While all of the species of Dorstenia produce furanocoumarins, this ability is found in only a small percentage of Ficus species. The evolutionary relationships within the Moraceae are still in question (42), but it is generally agreed that Dorstenia is an evolutionary advanced genus in the family. It is possible and even probable that the ancestor to this genus possessed the ability to synthesize furanocoumarins. It may even be possible that Dorstenia evolved from a furanocoumarin-producing species of Ficus. 

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