Thiacalix[4]arene Derivatives Bearing Imidazole Units: A Ditopic Hard/Soft Receptor for Na <sup>+</sup> and K <sup>+</sup> /Ag <sup>+</sup> with an Allosteric Effect and a Reusable Extractant for Dichromate Anions
Bibliographic record
Abstract
Abstract Two novel receptors 5,11,17,23‐tetra‐tert‐butyl‐25,27‐bis[(ethoxycarbonyl)methoxy]‐26,28‐bis‐[1‐methyl‐(imidazole)meth‐oxy]‐2,8,14,20‐tetra‐thiacalix[4]arene ( L1 ) and 5,11,17,23‐tetra‐tert‐butyl‐25,27‐bis‐[(benzyl)methoxy]‐26,28‐bis‐[1‐methyl‐(imidazole)‐methoxy]‐2,8,14,20‐tetrathiacalix[4]arene ( L2 ) possessing imidazole moieties based on thiacalix[4]arene in the 1,3‐ alternate conformation have been synthesized and characterized. The crystal structures of L1 and L2 have been determined. The binding behaviour towards Li + , Na + , K + and Ag + ions has been examined by 1 H NMR titration experiments in (CDCl 3 /CD 3 CN; 10:1, v/v) solution. The exclusive formation of mononuclear complexes of L1 with metal cations is of particular interest revealing a negative allosteric effect in the thiacalix[4]arene family. Liquid‐liquid extraction experiments indicate that synthesized L2 can be utilized as an efficient reusable extractant for dichromate anion by controlling the pH of the aqueous solution.
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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) | 0.001 | 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".