The studies on the chemistry of mitomycins are described : i) identification and structural elucidation of mitomycins D, E, F, G, I, J, K, L, M, albomitomycin A, and isomitomycin A from the fermentation broth; ii) derivation of mitomycins structurally close to naturally occurring mitomycins; iii) mitomycin rearrangement, the interconversion between mitomycin A, albomitomycin A, and isomitomycin A;iv) chemical con-version of isomitomycin A from mitomycin A; v) 3α-alkoxymitomycins, unexpected by-products in decarbamoylation of mitomycins;vi) the configuration of mitiromycin.