Bibliographic record
Abstract
The α-amanitin is an excellent template for use in the design of a chemical library on solid phase in order to study the mechanisms involved in the regulation of transcription. Indeed, α-amanitin selectively inhibits with high affinity the RNA Polymerase II. The α-amanitin belongs to the amatoxin family which is characterized by a defined rigid bicyclic structure consisting of a head-to-tail cyclized octapeptide, with a transannular linkage known as a tryptathionine bridge. The latter is made via the Savige-Fontana tryptathionylation of the oxidized tryptophan derivative 3α-hydroxypyrrolo[2,3-b]indoline in neat TFA. Therefore, in order to achieve the synthesis of an α-amanitin-based library on solid phase, the linker must be stable both in TFA and during the peptide synthesis. Such a linker was found in the tartrate-based linker. As proof of this concept, following completion of the linker synthesis on solid phase, the linear octapeptide precursor of Pro²-Glu³-S-deoxo-amaninamide was prepared by standard Fmoc/tert-Bu SPPS. The tryptathionine bridge was achieved by the Savige-Fontana reaction and the second cyclization was performed by a head-to-tail macrolactamization, all on PEGA resin. The bicyclic octapeptide was cleaved off from the linker with the mild sodium periodate oxidant, purified by RP-HPLC and characterized by HRMS (ESI) and UV spectra.
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) | 0.000 | 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) | 0.002 | 0.002 |
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".