Der Stoffwechsel von Verbindungen mit Dreifachbindung. VI. Stoffwechselverhalten von Alkincarbonsäuren und Alkindicarbonsäuren

Metabolism of Acetylenic Monocarboxylic and Dicarboxylic Acids Feeding of acetylenic monoacids with chain length of 11 to 18 C-atoms to rats led to excretion of dicarboxylic acids with retained triple bonds. 10-Octadecynoic acid led to the formation of metabolites with even and odd number of C-atoms, suggesting in addition to established ω- and β-oxidation an α-oxidative pathway.     

Die Redox-Eigenschaften von Hydroxyanthrachinonsulfonsäuren II

The formation of intermediates in the reduction of two hydroxyanthraquinonesulphonic acids has been investigated by potentiometric and polarographic techniques. Acid-base properties of molecules in the redox sequences have been deduced. In certain pH regions measurements were hindered by specific physical and chemical side-reactions. Reduction in strongly alkaline solution only produces semiquinone free radical intermediates, but below pH 10 bimolecular quinhydrones may also be formed.     

Zur Synthese von 3-Desoxy-aldulosonsäuren

The condensation of 2.4-ethylidene-erythrose with the sodium salt of diethyl-phosphono-piperidino-ethylacetate yields an enamino-lacton V which is converted under mild conditions into an α-keto ester, 2-oxo-3-desoxy-gluconic acid, and its quinoxaline derivative.     

Darstellung und Eigenschaften von Chlorozinksäuren

Contributions to the Chemistry of Hydrazine and its Derivatives. 53. Synthesis of P-, As-, and Sb-substituted Hydrazines by Addition of P? H, As? H, and Sb? H Groups to N?N Double Bonds Addition of diphenylphosphinous acid, diphenylthiophosphinous acid, methyl hydrogen phenylphosphonite, diethyl hydrogen phosphite, diphenylphosphane, dibutylphosphane, diphenylarsane, diethylarsane, and diphenylstibane to the N?N double bond of diethyl azodicarboxylate, dimethyl azodicarboxylate, ethyl phenylazocarboxylate, and azobenzene yields the P-, As-, and Sb- substituted hydrazines 1–23 . The spectroscopic data agree with the structural formulae. The course of the reactions suggests a polar reaction mechanism except in the case of the synthesis of 15 , which probably proceeds via radical intermediates. The azo systems employed show a distinct graduation in their ability to add to the element-hydrogen groups used.     

Synthesen von Phosphonocarbonsäuren durch Michael-Addition

Syntheses of Phosphono-carboxylic Acids by Michael Addition A number of phosphono-carboxylic acid esters are available by means of alkaline catalytic addition of P? H and C? H acidic esters to activated double and triple bonds. These may be transformed into complexing agents by hydrolysis.