Pyrazolo[3,4-<i>b</i>]pyridine in heterocyclic synthesis: synthesis of new pyrazolo[3,4-<i>b</i>]pyridines, imidazo[1',2':1,5]pyrazolo[3,4-<i>b</i>]pyridines, and pyrido[2',3':3,4]pyrazolo[1,5-<i>a</i>]pyrimidines
Bibliographic record
Abstract
Pyrazolo[3,4-b]pyridine derivatives 7 and 9 were synthesized via the reaction of 3-amino-1H-pyrazolo-[3,4-b]pyridine derivative 2 with ω-bromoacetophenones. Reaction of 7 and 9 with Ac2O afforded the imidazo[1',2':1,5]py razolo[3,4-b]pyridine derivative 8 and pyrazolo[3,4-b]pyridine derivative 10, respectively. Reaction of 2 with chloroacetonitrile followed by DMF-DMA gave imidazo[1',2':1,5]pyrazolo[3,4-b]pyridines 4 and 5, respectively. Acetyl acetone and 1,1-dicyano-2,2-dimethylthioethene were reacted with 2 to afford the pyrido[2',3':3,4]pyrazolo-[1,5-a]-pyrimidines 11 and 14, respectively. Also, 2 reacted with DMF-DMA to yield the formamidine 15, which in turn, reacted with active methylene reagents, yielding the corresponding pyrido[2',3':3,4]pyrazolo[1,5-a]pyrimidines 18 and 23a-23d.Key words: 1H-pyrazolo[3,4-b]pyridines, imidazo[1',2':1,5]pyrazolo[3,4-b]pyridines, pyrido[2',3':3,4]pyrazolo[1,5-a]pyrimidines.
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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) | 0.002 | 0.001 |
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".