Vergleichende Phytochemie als biologische Disziplin

Abstract

The great diversity of secondary compounds is interpreted as a typical expression of plant life representing an important survival strategy. Because of the toxicity of accumulated secondary metabolites for the plant itself, special depot areas and facilities which enable the transport against the energy gradient are needed for storage. Since all of these requisites and the biosynthetic pathways are more or less genetically fixed, the different accumulation tendencies and distribution of secondary compounds may serve as valuable chemotaxonomic criteria. Apart from systematically and ecologically oriented contributions, data derived from comparative analyses are also shown to be of practical value: e.g. the knowledge of taxon-specific biogenetic trends allows the prediction of the occurrence of distinct classes of substances even in those species of a group which have not been chemically investigated. This may play a prominent role in the search for distinct pharmaceutically active substances. Biogenetic investigations within a class of compounds advance rapidly when the structures of several derivatives occurring in related taxa are compared, etc. Ideas concerning the role of comparative phytochemistry as a biological discipline are outlined. A comparative computerized UV-IR data screening programme is described which allows a rapid preliminary identification of related derivatives within different classes of substances also representing a convenient method for the determination of characteristic biogenetic trends. The structure elucidation of several alkamides is discussed in detail on the basis of comparative IR-analyses.