Biomimetic decarboxylative condensation between malonate and acetate units attached to a glycoluril template
Bibliographic record
Abstract
Compound 10 (3,4,7,8-tetramethyl-2,5-dithioglycoluril) was converted in two steps to 12a, which contains a malonate and acetate unit attached to N1 and N6, respectively. These two groups are held in proximity in a manner analogous to the loaded ketosynthase domain of polyketide and fatty acid synthases. After cleavage of the methyl ester by pig liver esterase (PLE), a polar intermediate assigned to acid 15 was separated. This material undergoes conversion to acetoacetylglycoluril 18 upon attempted isolation. The overall conversion thus resembles the decarboxylative condensation catalyzed by ketosynthase. Furthermore, isotope labeling and product studies support a mechanism in which decarboxylation of 15 precedes an intramolecular Claisen-like condensation, as it is believed to occur for the ketosynthase enzymic case. The system thus provides a functional chemical model of the key carboncarbon bond-forming step in fatty acid and polyketide biosynthesis.Key words: biomimetic, decarboxylation, polyketide, esterase, Claisen condensation.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
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 | 0.000 | 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) | 0.001 | 0.001 |
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".