Reactivity of 2-Ethoxyquinazolin- 4-yl hydrazine and its Use in Synthesis of Novel Quinazoline Derivatives of Antimicrobial Activity
Bibliographic record
Abstract
The reactions of 2-ethoxy-4-hydrazinoquinazoline 2 with diethyl oxalate and ethyl chloroacetate gave 6-ethoxy-2H-[1,2,4]triazino[4,3-c]quinazoline-3,4-dione 3 and 6-ethoxy-2,3-dihydro-4H-[1,2,4]triazino[4,3-c]quinazolin-4-one 4 respectively. A series of 5-ethoxy-2-X-[1,2,4]triazolo[1, 5-c]quinazolines 5a-d was also produced by reacting 2 with the acid chlorides namely: benzoyl, crotonyl, cinnamyl and 2-furoyl chlorides via Dimroth rearrangement. Also, 2 reacted with ethyl chloroformate giving 6. Condensation of 2 with acetone gave Schiff base 7, and with monosaccharides gave the sugar hydrazones 8a-e which were thereafter acetylated giving the corresponding 9a-e. Cyclization of 8a-e by iron(III) chloride gave triazoloquinazolines 10a-e acyclic C-nucleosides which, by acetylation, afforded 11a-e. All products were confirmed by elemental, IR, MS, and 1H-NMR analysis. Products 8-11 were chosen for biological screening test against gram(+ ive) and gram(- ive) bacteria.
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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) | 0.000 | 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 | 0.001 |
| 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".