Mutagenicity of some derivatives of dipyrido[1,2-a:3',2'-d]imidazoles in Salmonella typhimurium with metabolic activation by rat liver and small intestine subcellular fractions.

The mutagenic effect of 2-amino-dipyrido[1,2-a:3',2'-d]imidazole (Glu-P-2) was compared with that of the 3-amino, 3-nitro, or 3-N-hydroxylated derivatives of the same base ring with methyl groups at positions 4 and 6 of the molecule. The compounds were tested in Salmonella typhimurium strain TA98 without metabolic activation and in the presence of different concentrations of subcellular fractions from livers or small intestines of rats pretreated with different P448/P450 inducers. The 4,6-dimethyl compounds are always more mutagenic than Glu-P-2.

Mutagenicity of several derivatives of dipyrido[1,2-a:2',3'-d]imidazoles.

Different derivatives of dipyrido[1,2-a:2',3'-d]imidazoles have been investigated, as mutagens for Salmonella typhimurium. The nature of different substitution groups and their positions on the base ring influenced markedly the mutagenicity of these compounds. From this structure/effect relationship study, it was demonstrated that the 2 and 3 positions were of special interest.