It is known that aromatic 3,3-dimethyltriazenes, when injected intraperitoneally, are capable of reaching tumor cells within 15-30 min and can be detected in unchanged form in the cell nuclei and cytoplasm of the tumors [5]. Considering the low ability of cells of various organs (including tumor cells) in contrast to liver cells, to metabolize (N-demethylate)3,3-dimethyltriazenes [6], it seemed interesting to us to make a comparative study of the influence of triazenes and the corresponding diazo-compounds generated by them on the activity of the key elements of metabolism.