Lignans in resin of Araucaria angustifolia by gas chromatography/mass spectrometry

Total extract of resin from Araucaria angustifolia was analyzed by gas chromatography/mass spectrometry and 32 lignans were identified. Lignan acetates are present in the resin and consist of four secoisolariciresinol acetates, six lariciresinol acetates, two 7'-hydroxylariciresinol acetates and an isolariciresinol acetate, which have hitherto not been reported in the plant kingdom. Shonanin and 7'-hydroxylariciresinol type lignans are also present in A. angustifolia resin. Lignans containing syringyl moieties, characteristic for angiosperms, occur in the resin and consist of 5-methoxylariciresinol-9-acetate, 5'-methoxylariciresinol-9-acetate, 5-methoxypinoresinol dimethyl ether and 5-methoxypinoresinol. This is noteworthy because syringyl moieties have only been reported for Thuja species (Cupressaceae) among the gymnosperms. The mass spectra of the various lignan trimethylsilyl derivatives are discussed with the interpretations of the fragmentation patterns.