Lignans in resin of <i>Araucaria angustifolia</i> by gas chromatography/mass spectrometry
Bibliographic record
Abstract
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.
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".