Aniline citrate preparation

Ravdin and Crandall (695) isolated a protein fraction from rat liver which converted homogentisic acid to a jS-keto acid decarboxylated slowly by aniline citrate at 38°C. A second enzyme fraction was obtained which converted this keto acid to acetoacetic acid. The /3-keto acid was isolated as its silver salt and was found also to be a dicarboxylic acid and a /3-diketone, and to give fumaric and acetoacetic acids on hydrolysis. The proposed formulation as fumarylacetoacetic acid (see diagram 8) has since beeri amply confirmed. Conversion of homogentisic acid to fumarylacetoacetic acid by a liver preparation involves uptake of the expected two atoms of oxygen (e.g., 489, 523). 

Fig. 2.16. Plot of the current recorded at +0.1 V at a poly(aniline)/poly(vinylsulfonate)-coated glassy carbon electrode (deposition charge ISO mC, geometric area 0.38 cm2) rotated at 9 Hz in 0.1 mol dm-3 citrate/phosphate buffer at pH 7 as a function of the NADH concentration. The currents are corrected for the background current (<0.2 p.A) in each case. Data for three different films prepared under identical conditions are shown. The inset shows the current for oxidation of NADH at +0.1 V at an uncoated glassy carbon electrode treated identically to the coated electrode except that no aniline monomer was added to...

N-(4-Piperidyl) propioanilide is prepared by the condensation of propionyl chloride with N-(4-piperidyl)-aniline. The resulting product is further condensed with phenethyl chloride to obtain the corresponding fentanyl base which on reaction with an equimolar portion of citric acid gives rise to the (1 1) citrate. 

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