Lack of Influence of the Carbamoyl Group on the Stereochemistry of the Acid-Catalyzed Opening of the Aziridine Ring of the Mitomycins and of Congeners

Article abstract of DOI:10.1021/jm00379a008

The acid-catalyzed opening of the aziridine ring of mitomycins A and C is known to occur predominantly with cis stereochemistry.We have observed that the presence or absence of a carbamoyl group at C-10 of mitomycin C and in certain of its analogues does not have a significant influence on the stereochemistry of the opening of this ring.The trans product obtained from mitomycin C was shown to be stable when treated with acid under the conditions of its formation.Mitomycin B was also shown to yield predominantly the cis product when it was subjected to acid-catalyzedopening of its aziridine ring.The 1H NMR spectra of acetate derivatives prepared from mitomycin B show two sets of signals that are due to two populations of rotamers.The analysis of these spectra has substantiated several previous spectral assignments.This paper also presents some thoughts on acid-catalyzed bifunctional DNA alkylation by mitomycins and 10-decarbamoyloxy-9-dehydromitomycins.