We wish to report (1) that photoisomerization of pyridine to a Dewar pyridine, 2-azabicyclo[2.2.0]hexa-2,5-diene (I), occurs in the liquid phase at 2537 Á; (2) that photoreduction of pyridine occurs in aqueous sodium borohydride, yielding 2-azabicyclo[2.2.0]hex-5ene (II), and (3) that I is an intermediate in the formation of II, as well as in the photohydration2 of pyridine to 5-amino-2,4-pentadienal (III). The Dewar pyridine, which is the first valence isomer of pyridine or its derivatives to be found,3 reverts completely to pyridine within 15 min at room temperature, but fortunately has a high activation energy, 16 kcal mol-1, for rearomatization. The picolines and several lutidines also form thermally unstable photoisomers which are reduced by borohydride and hydrolyzed by water.

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Background The value of patient-reported outcomes (PRO) is increasingly recognized in patient-centered care. Longitudinal data collection may be challenging and cost prohibitive. Automation of PRO collection may complement routine clinical follow-up, especially for procedures aiming to improve quality of life, such as atrial fibrillation (AF) ablation. Methods We aimed to develop a fully automated platform to collect PRO and evaluate its first clinical application in a prospective cohort of AF ablation. The duration of follow-up and data availability were assessed with automated PRO and routine follow-up versus routine follow-up alone (primary outcome). Quality of life and healthcare utilization (secondary outcomes) by PRO were assessed. Results Between 2013 and 2016, 2175 patients were eligible to receive 10 903 PRO assessment invitations, and the automated platform sent all invitations as programmed. More follow-up assessments were obtained with automated PRO and routine follow-up compared with routine follow-up alone (12 859 versus 10 248; P <0.0001) which allowed longer duration of follow-up (378 versus 217 days, 74% increase; P <0.0001). By automated PRO, a large number of disease-specific variables were collected and showed improvement in quality of life (baseline median AF symptom severity score AFSSS of 12 [6–18] and ranged between 2 and 3 on subsequent assessments; P <0.0001). This improvement was also true for each of the AFSSS individual components ( P <0.0001). In PRO, there was a significant reduction in AF burden (such as frequency and duration of episodes; P <0.0001) and associated healthcare utilization (including emergency visits and hospitalizations; P <0.0001) after the ablation procedures. Conclusions A fully automated system for PRO collection enhanced clinical follow-up and allowed collection of disease-specific data when applied in a prospective cohort of AF ablation.

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Chiral stationary phases (CSPs) for liquid chromatography derived from N-(acyl)proline-3,5-dimethylanilides separate the enantiomers of N-(3,5-dinitrobenzoyl)-alpha-amino esters and amides with high levels of selectivity. These CSPs have been used to assemble a large body of chromatographic data which indirectly supports the validity of the mechanistic rationale originally used in the design of these CSPs. We herein report (1)H and (13)C chemical shift data obtained when the (S)-enantiomer of chiral solvating agent (CSA) 3, a soluble analogue of the selector used in CSP (S)-1, acts on each of the enantiomers of the dimethylamide of N-(3,5-dinitrobenzoyl)leucine, 2. The changes in chemical shift in the mixture of (S)-2 and (S)-3 support the existence of those interactions thought to be essential to chiral recognition in this system. In addition, significant intermolecular NOESY enhancements are observed in this mixture. These NOE data are consistent with the structure expected for the more stable diastereomeric adsorbate formed between (S)-2 and the (S)-proline-derived CSP 1. No intermolecular NOEs are observed for corresponding mixtures of the chiral solvating agent (S)-3 and (R)-2, the enantiomer least retained on (S)-CSP 1.

Die Photosolvatation von Benzol in sauren hydroxylhaltigen Lösungsmitteln (II) führt zu den endo‐ und exo‐Addukten (III) und (IV).