Terpenoids and more polar compounds from the male cones of Wollemia nobilis

The analysis of metabolites contained in the male cones of Wollemia nobilis was investigated for the first time in this study. Several diterpenoids of chemosystematic relevance were recognized for the first time from the genus and/ or from the Araucariaceae family, namely isocupressic acid (1), acetyl-isocupressic acid (2), methyl (E)-communate (3) and sandaracopimaric acid (4). All these terpenoids are also endowed with interesting biological activities and may play a primary role in the self defence toward herbivores. The presence of a new norlabdane (norlabda-8(16)-12-dien-14,17-diol) trivially named as wollemol (5) was also recognized. Norditerpenes are scarcely distributed in Plant Kingdom and in particular in Gymnosperms and this aspect was discussed. The structure of 5 was determined by extensive NMR analysis employing mono- and bidimensional experiments. The 7-4‴-dimethoxyagathisflavone (6), a biflavonoid already recognized in Araucariaceae and W. nobilis, was also isolated from male cones together with shikimic acid (7), a biogenetic precursor of polyphenolic compounds, besides carbohydrates such as glucose (8) and saccharose (9), and arginine (10) a quite common amino acid.