A proposed crystal structure of fruquintinib Form I, C <sub>21</sub> H <sub>19</sub> N <sub>3</sub> O <sub>5</sub>
Bibliographic record
Abstract
Abstract The crystal structure of fruquintinib Form I has been solved and refined using synchrotron X-ray powder diffraction data and optimized using density functional theory techniques. Fruquintinib Form I crystallizes in space group C2 (#5) with a = 35.4167(22), b = 3.90500(12), c = 26.9370(11) Å, β = 108.0290(22)°, V = 3,542.52(26) Å 3 , and Z = 8 at 298 K. The crystal structure consists of double layers of each of the two independent molecules parallel to the ab -plane. These layers stack along the short b -axis. N–H···N hydrogen bonds link the layers. Most of the C–H···N and C–H···O hydrogen bonds are intramolecular. The powder pattern has been submitted to ICDD for inclusion in the Powder Diffraction File ™ (PDF ® ).
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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) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.001 | 0.000 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.002 | 0.000 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.010 | 0.002 |
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".