O2-dependent cleavage of DNA by tetrazomine.

A mechanism for the reduction of molecular oxygen that results in the O2-dependent cleavage of both single-stranded and double-stranded DNA by the antitumor antibiotic tetrazomine (1) is presented. The results are discussed in the context of a redox self-disproportionation of the oxazolidine moiety of tetrazomine. Comparisons are made to the structurally analogous natural product quinocarcin (2) in which, like tetrazomine, the oxazolidine moiety is invoked in redox chemistry, which ultimately results in the reduction of molecular oxygen to superoxide.