Synthesis and photophysical properties of fluorophore-labeled abscisic acid
Bibliographic record
Abstract
The 8'-benzophenone, 8'-dansylhydrazone, 3'-S-(2-ethyldansylamide), and 3'-S-acetamidofluorescein derivatives of the plant hormone abscisic acid (ABA) have been synthesized for use in photoaffinity labeling (the benzophenone derivative) or fluorescence probe experiments and have been spectroscopically characterized. One of the three fluorescent compounds, the 3'-tethered fluorescein derivative, exhibits spectroscopic and photophysical properties which indicate that it could be an excellent fluorescent probe of ABA interactions in vivo. The 3'-tethered fluorescein and ABA moieties do not interact strongly, so that the fluorescence properties of the fluorescein-labelled hormone are very similar to those of fluorescein itself. Measurements of the absorption, emission, and fluorescence excitation spectra, fluorescence quantum yields, and fluorescence decay parameters of this derivative as a function of pH indicate that the photophysics is dominated by ground and excited state prototropic equilibria involving only the fluorescein moiety. The fluorescein dianion is the only significant absorber and emitter at pH > 6.7, whereas only the cation absorbs and emits at pH < 0. In the intervening pH range, strong emission from the monoanion and weak emission from two neutral species, tentatively assigned to the zwitterion and the lactone of the fluorescein moiety, is observed.Key words: abscisic acid, fluorescein, synthesis, photophysics.
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 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 | 0.000 | 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) | 0.003 | 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".