Influence of B-ring modifications on proton affinity, transmembrane anion transport and anti-cancer properties of synthetic prodigiosenes
Why this work is in the frame
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Bibliographic record
Abstract
Prodigiosin is the parent compound of the tripyrrolic natural products known as the prodigiosenes. Some of these natural products and their synthetic analogs show anti-cancer, immunosuppressive and antimicrobial actions, amongst other biological activities. One mechanism put forth to explain their biological activity is that since prodigiosenes are typically protonated at physiological pH they can alter intracellular pH via HCl co-transport (or Cl(-)/OH(-) exchange) across cell membranes. In this study we synthesized a series of prodigiosene analogs with different -O-aryl substituents attached to the B-ring of the tripyrrolic skeleton. NMR studies showed that these analogs can exist as a mixture of two stable α and β conformers in acidic solution, and that both conformers can bind anions in solution. We found that the electronic nature of the O-aryl substituent on the B-ring influences the rate at which these prodigiosenes catalyze transmembrane anion transport, i.e. the prodigiosenes with the higher pKa had greater Cl(-)/NO3(-) exchange rates. Four of the synthetic prodigiosenes were tested for their in vitro anti-cancer activities in the NCI60 human tumour panel. Despite their promising in vitro anti-cancer activity (GI50 values ranging from 18 to 74 nM), there was no evidence that this activity is influenced by the extent of protonation of these synthetic prodigiosenes.
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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) | 0.000 | 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 it