Oxidation of o-isopropylphenol with lead tetraacetate: Synthesis of the unit of celastroidin terpenes by the Diels-Alder condensation
Bibliographic record
Abstract
Lead tetraacetate oxidation of o-isopropyl phenol under various conditions led to the dienone acetate which, when dimerized, represents a central part of the celastroidin penta- and hexa-terpenes (natural products from the Mexican shrub Hippocratea Celastroides). Six oxidation products formed in this reaction (the iso-propyl dienolone acetate, two dimers, benzoquinone, and two phenol acetates) were identified with help of 2D and 3D NMR, GC and LC-MS. From this, we concluded that the dimer skeleton observed for the dienolone acetate in natural products corresponded to the product from the photochemical pathway, and that the synthetic dimer has the opposite geometry; this was verified by molecular modelling. The oxidation of the second compound, o-cresol, leads to a similar profile of products.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 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) | 0.000 | 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 teacher head, 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".