Mutagenicity and chemical reactivity of epoxidic intermediates of the isoprene metabolism and other structurally related compounds.

The mutagenic activities of the epoxidic intermediates of the isoprene biotransformation were investigated using Salmonella typhimurium and compared with those of other structurally related epoxides. The compound 2-methyl-1,2,3,4-diepoxybutane, chemically analogous to the well known carcinogenic 1,2,3,4-diepoxybutane, was found to be as mutagenic as the latter. Moreover, the mutagenic activities of oxiranes were correlated to their alkylating powers towards nicotinamide and to their half-lives for spontaneous hydrolysis. The relationship between alkylating power and mutagenicity was found to hold for the stable epoxides that react mainly by an SN2 substitution mechanism.