Pyrimidine-Fused Heterocyclic Frameworks Based on an N4-Arylcytosine Scaffold: Synthesis, Characterization, and PNA Oligomerization of the Fluorescent Cytosine Analogue 5,6-BenzopC
Bibliographic record
Abstract
A synthesis of an intrinsically fluorescent cytosine analogue 5,6-benzopC has been developed utilizing the reductive Ni-mediated cyclization of an N4-aryl,N4-(Boc)cytosine intermediate as a key step. 5,6-BenzopC was found to possess interesting fluorescence properties (Φ = 0.79, EtOH; Stoke's shift 113 nm). Peptide nucleic acid (PNA) oligomerization of the 5,6-benzopC monomer was carried out, followed by hybridization studies with complementary deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) which showed the modification to be well tolerated in the sequence contexts examined. Initial attempts to synthesize the heterocyclic skeleton present in 5,6-benzopC resulted in the discovery of routes to the pyrimido[1,6-a]benzimidazole, pyrimido[1,6-a]quinazoline, and pyrimido[1,6-a]benzo[b]6-bora-1,3-diazine heterocyclic frameworks.
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 | 0.000 | 0.001 |
| 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) | 0.000 | 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".