Synthesis and characterization of novel conformers of ( <i>E</i> ) <i>‐</i> 2‐(3‐nitro‐ <i>H</i> ‐imidazo[1,2‐ <i>a</i> ]pyridin‐2‐ylthio)‐ <i>N</i> ′‐benzylideneacetohydrazide derivatives
Bibliographic record
Abstract
Abstract Eighteen new N ‐acylhydrazones ( 9a–r ) containing the imidazo[1,2‐ a ]pyridine scaffold were synthesized through a seven steps reaction sequence, ending with a condensation of 2‐(3‐nitro‐ H ‐imidazo[1,2‐ a ]pyridin‐2‐ylthio)acetohydrazide with various benzaldehyde derivatives ( 8a–r ). All synthesized compounds were characterized by 1D NMR ( 1 H and 13 C NMR) and 2D NMR (NOESY) spectroscopic analyses and high‐resolution mass spectrometry (HRMS). The analysis of 1 H NMR data performed at room temperature in deuterated dimethylsulfoxide (DMSO‐ d 6 ) revealed the presence of ( E ) ‐ 2‐(3‐nitro‐ H ‐imidazo[1,2‐ a ]pyridin‐2‐ylthio)‐ N ′‐benzylideneacetohydrazide ( 9a–r ) as a mixture of two conformers, namely, syn‐periplanar E ( sp E ) and anti‐periplanar E ( ap E ). For all N ‐acylhydrazones that were synthesized, the sp E conformer was found to be the major form except in the case of hydrazone derived from o ‐hydroxybenzaldehyde.
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) | 0.000 | 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".