Methyl‐substituierte carbocyclische Aromaten der Benzol‐, Diphenyl‐, Terphenyl‐, Stilben‐, 1,4‐Diphenylbutadien‐, Tolan‐, 1,4‐Diphenylbutadiin‐, Naphtalin‐, Anthracen‐und Phenanthren‐Reihe werden mit Anilen aromatischer Aldehyde in Dimethylformamid in Gegenwart von Kaliumhydroxid oder Kalium‐t‐butylat zu Styryl‐Derivaten umgesetzt.

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Mit 1 Textfigur.) i (Vorgelegt in der Sitzung am 8. Februar 1912.) 121ber die Einwirkung von Diamid auf die Ester der Pyridincarbons/iuren liegen bisher nut zwei Arbeiten vor: Curtius und Mohr i haben das Nikotins/iurehydrazid und einige seiner Derivate, und Mohr -~ und Amos a die entsprechenden Verbindungen aus Lutidindicarbons~iure, und deren Abbau zu ,Diamino-und Dioxylutidin beschrieben. Da jetzt durch die Patente yon Raschig das Hydrazinhydrat zu einem leicht zug/inglichen Reagens geworden ist, haben wir seine Verwendbarkeit for die n/ihere Charakterisierung der Pyridinmono-und Dicarbons/iuren geprtift. Die untersuchten Verbindungen sind nun im allgemeinen leicht darstellbar und krystallisieren gut, was namentlich ffir die ~-Reihe bemerkenswert ist, die sonst (mit Ausnahme des Nikotins/turemethylesters) schlecht krystallisierende Vertreter liefert. Es mul3 aber hervorgehoben werden, daf3 die Hydrazinderivate der Pyridinreihe sich nut dann gut darstellen lassen, wenn man reines Ausgangsmaterial verwendet; so konnten wit nur aus Nikotin eine S/lure erhalten, die die yon Curtius und 1

Purpose: To evaluate the diagnostic benefit of time-resolved CENTRA-keyhole contrastenhanced cardiovascular magnetic resonance angiography (CE-CMRA) for improving arterialvenous separation of pulmonary vessels. Methods: Twenty-three patients (18 males; age = 58 ± 11y) after radiofrequency pulmonary vein isolation to treat atrial fibrillation were examined using CENTRA-keyhole based multi-phase 3D CE-CMRA yielding 6 near-isotropic 3D datasets every 1.6 s (50-60 coronal partitions, 1.4 × 1.4 × 1.3 mm, SENSE-factor 3). Results were compared with conventional non-keyhole CE-CMRA (identical parameters, SENSE-factor 2). Results: Data acquisition was accelerated by a speedup factor of ∼9 compared with the reference CE-CMRA (SENSE 1.5 * , keyhole 6 * ). No pulmonary venous stenoses were detected by either method, overall pulmonary venous diameters were 17.1 ± 3.6 mm. Applying Bland-Altman analysis, vessel diameters differed by a mean of 0.1 mm + 2.1 mm/−2.0 mm (mean ± 2 SD), indicating close agreement between both techniques. Interobserver variability was higher for CENTRAkeyhole (mean = 0.1 mm; mean ± 2 SD: +2.5 mm/−2.3 mm) compared to conventional technique (0.0 mm; +1.6 mm/−1.5 mm), corresponding to a percentual deviation (mean ± 2 SD) of the mean diameter of approximately ± 15% (keyhole CE-CMRA) and ± 10% (conventional CE-CMRA), respectively. Using keyhole-based time-resolved CE-CMRA, the contrast between pulmonary veins versus aorta/pulmonary artery was significantly increased (p < 0.05), which improved vessel depiction. In 12 cases, the contrast bolus arrival was delayed in one of the pulmonary veins by 1 dynamic frame (= 1.6 seconds); in 7 cases by 2 frames (= 3.2 seconds) and in 1 subject by 3 frames (= 4.8 seconds). The bolus usually appeared first in the upper right pulmonary vein whereas a delay occurred most often in the lower left pulmonary vein. Conclusions: Conventional CE-CMRA may be advantageous for accurate vessel size measures as evidenced by superior interobserver reproducibility in this study. Multi-dynamic CE-CMRA using CENTRA-keyhole with SENSE, however, allows for improved arterio-venous separation of pulmonary vessels and additional dynamical information on pulmonary venous perfusion, while maintaining high spatial resolution. Exact bolus timing is no longer needed.

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