Influence of Albumin Concentration in the Foetal Circulation on the Placental Transfer of 2,2′,4,4′,5,5′-Hexachlorobiphenyl in the Guinea-pig

Abstract: Placental transport of 2,2′,4,4′,5,5′-hexachlorobiphenyl in the guinea-pig was studied by means of perfusion technique. This transfer was rapid when heparinized blood was used as perfusion medium. The same concentration of the chlorobiphenyl in both maternal and foetal compartments was achieved about 20 min. after start of infusion. It was also shown that when dextran solution or dextran solution with addition of Intralipid^® to the same concentration as the total lipid concentration in blood, were used as perfusion medium, there was no placental transport of the chlorobiphenyl. Furthermore, it was shown that the placental transport of the chlorobiphenyl was strongly dependent on the albumin concentration, but independent of the γ-globulin concentration in the perfusion medium.     

A facile synthesis of deuterium labeled 2,2‐dimethyl‐[2H6]‐succinic acid and its anhydride

Deuterium labeled 2,2‐dimethyl‐[²H₆]‐succinic anhydride by a sequence of reactions involving Knoevenagel condensation of [²H₆]‐acetone with ethyl cyanoacetate in the presence of piperidine, Michael addition of cyanide, HCl hydrolysis, simultaneous decarboxylation, and subsequent dehydration using acetic anhydride in an overall yield of 34.23% based on [²H₆]‐acetone utilized in the reaction is reported. The title compounds were characterized and confirmed spectroscopically by Fourier transform infrared, ¹H‐NMR, and Mass. The chemical purity as determined by HPLC was 99%. To the best of our knowledge, the synthesis of these specifically deuterium labeled compounds has not been reported so far.