SYNTHESIS OF 2-PYRROLECARBOXYLIC (C14O2H) ACID AND STUDY OF ITS METABOLISM IN THE INTACT RAT

A method is described for the synthesis of 2-pyrrolecarboxylic (C14O2H) acid (PCA), in 50% over-all yield, by carbonation in a closed system of pyrrylmagnesium bromide, using a small amount of radioactive carbon dioxide. Doses of the labelled substance were administered by intraperitoneal injection to young rats. A small fraction of the injected radioactive PCA was catabolized in the rat tissues in such a manner that only 5 to 6% of the isotope appeared in expired carbon dioxide within 24 hours. From 70 to 80% of the injected radioactivity was excreted in the urine collected for 24 hours. Unchanged PCA, pyrroylglycine, and a glucuronide of PCA were the three major radioactive products demonstrated in the urine.