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Planta Med 1984; 50(5): 380-385
DOI: 10.1055/s-2007-969743
Research Articles

© Georg Thieme Verlag Stuttgart · New York

Chemosystematics of the Gnetatae and the Chemical Evolution of Seed Plants1

Otto R. Gottlieb2 , Klaus Kubitzki3
  • 2Instituto de Química, Universidade de São Paulo, 05508 São Paulo SP, Brazil
  • 3Institut für Allgemeine Botanik und Botanischer Garten der Universität Hamburg, Ohnhorststr. 18, D-2000 Hamburg 52
1 Dedicated to Prof. Dr. R. Hegnauer on the occasion of his 65th birthday
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1984

1984

Publication Date:
26 February 2007 (online)

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Abstract

A survey of the secondary metabolites reported for Ephedra, Welwitschia and Gnetum documents a far-reaching chemical similarity of these genera with the angiosperms. However, the different substitution patterns of the phenolics do not support a close phylogenetic link between the two groups. The most significant chemical difference between the Gnetatae and the angiosperms seems to be the widespread use of protective devices against oxidation such as O-methylation and formation of Schiff bases which are so frequent in angiosperms and nearly absent from the Gnetatae and other gymnosperms.