Cucurbit[7]uril host-guest complexes with cationic bis(4,5-dihydro-1<i>H</i>-imidazol-2-yl) guests in aqueous solution
Bibliographic record
Abstract
The host–guest interactions between cucurbit[7]uril and a series of novel cationic bis(4,5-dihydro-1H-imidazol-2-yl)arene and 1-(4,5-dihydro-1H-imidazol-2-yl)- and 1,3-bis(4,5-dihydro-1H-imidazol-2-yl)-adamantane guests have been investigated in aqueous solution using UV–vis and NMR spectroscopy, and electrospray mass spectrometry. With the exception of the 1,3-bis(4,5-dihydro-1H-imidazol-2-yl)adamantane (which binds externally to the CB[7]), these guests form very stable inclusion complexes with slow exchange on the 1H NMR timescale. The direction and magnitude of the complexation-induced shifts (CIS) in the proton resonances of the guests are indicative of the residence of the hydrophobic core of the guest within the CB[7] cavity and the charged 4,5-dihydro-1H-imidazol-2-yl units outside the cavity adjacent to the carbonyl-lined portals of the host. The CIS values and the inclusion stability constants have been correlated with the nature of the guest core and with the distance between the charges on the terminal 4,5-dihydro-1H-imidazol-2-yl rings.Key words: cucurbit[7]uril, host–guest complex, dihydroimidazolyl, inclusion stability constants.
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 | 0.001 | 0.000 |
| Research integrity | 0.000 | 0.001 |
| Insufficient payload (model declined to judge) | 0.001 | 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 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".