RELATIVE REACTIVITIES OF AMINO-ACIDS IN THE FORMATION OF PYRIDINES, PYRROLES, AND OXAZOLES

The contributions of N-15-labeled glycine and tested amino acids (glutamine, glutamic acid, asparagine, aspartic acid, lysine, arginine, phenylalanine, and isoleucine) to pyridine, pyrrole, and oxazole formation were investigated. Ten pyridines, nine pyrroles, two oxazoles, three amines, and one benzonitrile were identified in the present study. The quantities of pyridines, pyrroles, and oxazoles in the reaction mixture of glycine and aspartic acid were the highest. Aspartic acid, lysine, and asparagine had the highest contribution in pyridine, pyrrole, and oxazole formation, respectively. In the presence of glycine, glutamic acid showed the least contribution, whereas asparagine had the highest contribution to the formation of all nitrogen-containing compounds among the tested amino acids. While lysine was able to increase the reactivity of glycine, arginine inhibited the capability of glycine to produce nitrogen-containing volatile compounds.