Influence of the C‐terminal substituent on the crystal‐state conformation of Adm peptides
Bibliographic record
Abstract
Abstract The bis‐functionalized diamondoid α‐amino acid 2‐aminoadamantane‐2‐carboxylic acid (Adm) has been used as the building block of four Nα‐formyl homo‐dipeptide alkylamide sequences via a solution‐phase Ugi multicomponent reaction approach. The conformers of these peptides have been determined in the crystalline state by X‐ray diffraction to distinguish the influences of the C‐terminal substituent. One of the Adm peptides folds into an open and a hydrogen‐bonded γ‐turn geometry. Moreover, 3D‐structures have been observed featuring two consecutive γ‐turns in an incipient γ‐helical structure, a significantly distorted nonhelical β‐turn, as well as an S‐shaped conformation with opposite helical screw senses. A significant topological variety is thus exhibited by the ‐Adm‐Adm‐ sequences contingent on their C‐terminal substituents, illustrating both the broad conformational potential and the need for further characterization of this sterically bulky residue in explorations of its ϕ, ψ space.
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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 | 0.000 |
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".