Mitomycin C: Chemical and Biological Studies on Alkylation

Abstract
The presence of an aziridine ring in mitomycin C suggests that the mechanism of action of the antibiotic is like that of the antitumor alkylating agents. However the compound is unexpectedly stable during aerobic incubation with rat liver homogenates although rapidly metabolized anaerobically. Mitomycin is not reactive with γ-(4-nitrobenzyl) pyridine and reacts only slowly at acid pH with thiosulfate. It is proposed that mitomycin is activated in vivo, possibly by a reduction which "unmasks" the potential activity of the fused aziridine ring.