Classification of Natural Products

The intense need for herbal information in response to consumer interest in natural products was an acute reminder that information and knowledge generated locally have an international role. Confusion created by multiple names and unreliable nomenclature and classification of natural products mirrors problems encountered with drug nomenclature in the 1960s. Our information deficit in this area is still large. Chapter 24 presents a discussion of natural products. 

The classification of natural products may follow the four schemes below ... 

KochMA, SchuffenhauerA, ScheckM, etfl/. (2005) Charting biologically relevant chemical space A structural classification of natural products (SCONP). Proc. Natl. Acad. Set. 102 11111-11211. 

B. The scaffold tree for structural classification of natural products... 

Koch, M. A., Schuffenhauer, A., Scheck, M., Wetzel, S., Casaulta, M., Odermatt, A., Ertl, P, and Waldmann, H. (2005) Charting biologically relevant chemical space A structural classification of natural products (SCONP). Proc. Natl. Acad. Sci. U.S.A. 102,17272-17277. 

For compound sets with a well defined limit, it is possible to enumerate all the scaffolds in the set and to visualise the chemical relationships. In particular, the Bioactivity guided Scaffold tree method (BIOS) provides a visually compelling means of exploring complex structural relationships. As an example, the Structural Classification of Natural Products (SCONP) arranges the scaffolds of the natural products in this tree-like fashion. This provides a concise and chemistry friendly description of natural product diversity. 

Figure 14.2 The Scaffold tree visualisation of the Structural Classification of Natural Products (SCONP). Reproduced from ref. 61, Waldman et al., Proc. Natl. Acad. Sci. 2005, 102, 17272. Copyright 2005 National Academy of Sciences, U.S.A.

The molecular scaffolds (ring systems) validated by nature or biology can be arranged into hierarchical clusters Structural Classification of Natural Products (SCONP) (Figure 1.2), which could accelerate the design... 

Dictionary of Natural Products Classification of Natural Products... 

Box 1 A functional classification of natural product biosynthetic enzymes. 

Waldmann et al. have performed a chemoinformatic analysis of all available natural product structures and classified fhe most frequent occurring scaffolds in a hierarchical tree (Structural Classification of Natural Products, SCONP) [115]. This analysis represenfs for fhe first time a quantitative description of privileged structures found among natural products. The Wald-... 

FIGURE 10.1. Location of polypropionates in the classification of natural products. 

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