Synthesis and vasodilator activity of 3,4-dihydropyrimidin-2(<i>1H</i>)-ones bearing urea, thiourea, and sulfonylurea moieties
Bibliographic record
Abstract
A series of novel 3,4-dihydropyrimidin-2(1H)-ones bearing urea, thiourea, and sulfonylurea moieties were synthesized and pharmacologically evaluated as vasodilator agents. The most interesting vasodilators were the thiourea derivatives 6a and 6b and the urea derivatives 6f–6i and 7f–7h, although the ureas were relatively more active than thioureas. Twenty-fold more active than diazoxide, the urea 6g was the most potent vasodilator (EC 50 = 0.983 ± 0.061 μmol/L) and proved to act as a voltage-gated calcium channel blocker. The lack of activity of sulfonylureas, 6k and 7j, could be attributed to their partial ionization at the physiological pH because of their acidic character. It should be interesting to investigate a larger number of compounds, including N-methylated sulfonylureas, to increase the vasodilator activity and to explore other biological models.
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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 | 0.000 |
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".