A Chemosystematic Overview of Pteridophytes and Gymnosperms

Abstract

On the following pages we have organized, in a systematic context, the mass of micromolecular information available for pteridophytes and gymnosperms, with the aim of investigating, from the chemosystematic point of view, the relationships among them. A complete literature survey for chemical constituents of these plants has become a task of gigantic magnitude. This became apparent from our effort in surveying all relevant entries in “Chemical Abstracts” relating to pteridophytes. Because of limitations in time, we were forced to extract the data for gymnosperms mostly from the standard reviews listed under “General References” (p. 14/15) and to rely heavily on our own, necessarily limited judgement, to produce as balanced a list of compounds as possible. Each of the structures was then classified according to its biosynthetic origin, as flavonoid, terpenoid and polyketide. Next, subclasses were recognized, each represented by a collection of compound types. Where appropriate, for relatively small collections, actual compounds, not compound types, were collections.