An Improved Procedure for the Preparation of the Endothelin-B-Receptor Ligand Sarafotoxin 6c
Bibliographic record
Abstract
Sarafotoxin 6c (S6c) is a specific agonist for the endothelin-B- (ETB) receptor, being largely used as a standard compound in pharmacological studies related to ETB-receptors. We have developed an improved peptide synthesis prncedure. Using the Fmoc chemistry methodology and an appropriate orthogonal protection scheme, we obtained a crude peptide with a major component identified as [Cys(Acm)(1,15)]S6c. A silver salt (AgBF4) treatment of this crude material completely removed the Acm moieties without the appearance of any major side-products. The free peptide was cyclized using a Fe3+/Fe2+ oxidizing method. Besides the formation of the bridges, no other modification was observed. Thus, the peptide purification was facilitated and an excellent yield of pure sarafotoxin was obtained. The material was characterized by analytical reverse phase-high performance liquid chromatography (RP-HPLC) and matrix assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry. Pharmacological properties of the peptide were evaluated in an ETB preparation (guinea pig lung parenchyma strips) and were identical to those of an S6c standard.
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 | 0.001 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.001 |
| 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".