Röntgen-Kontrastmittel. 16. Mitteilung. Derivate von jodierten Benzoylamino-phenyl- und Benzoylamino-phenoxy-alkansäuren

A number of new [(3-amino-2,4,6-triiodo-benzoylamino)-phenyl- and -phenoxy]-alkanoic acids have been synthesized for evaluation as X-ray contrast agents. The toxicity, the bilitropism, and the urotropism of these compounds were determined.     

Röntgenographische Hochtemperaturuntersuchung der Thermischen Zersetzung von Dodekawolframatoborsäure

Investigation on the Thermal Degradation of 12-Tungstoboric Acid by Means of X-ray Heating Photographs By means of X-ray Guinier investigation of 12-tungstoboric acid hexahydrate H₅[BO₄W₁₂O₁₂] · 6H₂O at room temperature a monoclinic lattice was determined, being in disagreement with the literature. The LSQ-refinement of parameters of the monoclinic C-lattice give a = 1.728 nm, b = 1.215 nm, c = 1.216 nm, b? = 135° 34′, Z = 2, d_exp. = 5.44 g cm^?3, d_calcd. = 5.52 g cm ^?3. From X-ray heating patterns (heating rate: 4°C/min, atmosphere: air) the formation of a new monoclinic phase at 185°C was found, being stable till 270°C. From 270–420°C exist a bad crystalline phase and from 420–840°C a monoclinic phase: a = 0.532 nm, b = 0.389 nm, c = 0.522 nm, b? = 91° 09′. Above 840°C a tetragonal phase is formed with a diagram typical for pure WO₃. The relationship between the modifications is discussed.