Total synthesis of the cytotoxic cyclodepsipeptide (-)-doliculide: The “ester” effect in acyclic 1,3-induction of deoxypropionates
Bibliographic record
Abstract
The total synthesis of the marine cyclodepsipeptide (-)-doliculide is described. An acyclic (2S,4S,6R)-trimethyl alkanoic acid precursor to the "hydrocarbon" portion of doliculide was synthesized starting with l-ascorbic acid based on a stereocontrolled iterative conjugate addition of lithium dimethylcuprate to acyclic delta-Cmethyl alpha,beta-unsaturated ester derivatives. syn/syn selectivity was achieved by relying on 1,3-induction in preferred folded conformations that avoid 1,5-syn-pentane interactions in the transition states. The nature of the ester moiety seems to play an important role in determining the syn/anti ratios of C-methyl adducts. The 1-methyl-1-cyclopentyl ester group was found to confer the best syn selectivity to the cuprate addition products, especially in seven-carbon enoates.
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 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 | 0.002 | 0.005 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.001 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.001 | 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".