Introduction of Chirality into PNA By Replacement of the Achiral Methylene Carbonyl Linkage to the Nucleobase
Bibliographic record
Abstract
A novel approach to the introduction of chirality into peptide nucleic acid (PNA) by replacement of the methylene carbonyl linker by an alpha-amino acid derived moiety is described. A monomer compatible with Fmoc-based oligomerization chemistry possessing an L-serine derived linker has been synthesized and incorporated into PNA oligomers. A single, central substitution in a hexathymine PNA strongly destabilized triple helix formation whereas a central substitution in a mixed sequence is much better tolerated. We have investigated the influence of this substitution on the selectivity for strand composition (DNA versus RNA complement) and strand orientation (antiparallel versus parallel) in the context of duplex formation. A PNA 11-mer with a single substitution demonstrates a preference for an antiparallel RNA complement, as judged by thermal denaturation analysis of the complexes.
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 | 0.002 | 0.001 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.000 | 0.001 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.001 | 0.001 |
| 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".