Evolutionary aspects of caffeoyl ester distribution In Dicotyledons

Abstract

In this review, the distribution of phenylpropanoic acids in dicotyledons is visualized by using the Dahlgren diagram. Notably derivatives of caffeic acid show a close correlation with the taxonomic arrangement of plant families and orders. Generally, the hydroxycinnamic acids are ester bound to various alcohols, most frequently sugars, giving mono-, di- and trisaccharide esters. The monosaccharide esters are fairly common in all dicotyledons, whereas di- and trisaccharide esters occur exclusively in sympetalous orders. In these orders, rosmarinic acid and quinic acid esters, i.e. chlorogenic acid, have an alternative distribution to that of the disaccharide esters. Hence, chlorogenic acid is common in Asteraceae, Solanaceae and Rubiaceae, whereas rosmarinic acid and related compounds are restricted to Lamiaceae and Boraginaceae, and the disaccharide esters mainly to Scrophulariaceae and Oleaceae. Of more restricted occurrence are ferulic acid in Caryophyllales and derivatives with sinapic acid in Brassicaceae. The distribution is discussed in relation to the supposed evolution of chemical structures by derivation of intermediates in the biosynthetic route. Hence, the most derived compounds are found in the most remote groups of the Lamianae, e.g. Orobanchaceae.