Synthesis and mutagenicity of a new mutagen, 2-amino-1,7,9-trimethylimidazo[4,5-g]quinoxaline, and its analog.

A new mutagen, 2-amino-1,7,9-trimethylimidazo[4,5-g]quinoxaline (1), isolated from beef extract, was synthesized from 3-fluoro-2-methylaniline via an intermediate, 2,8-dimethyl-7-methylaminoquinoxaline (7a). Its 2-methylanalog (2) was also synthesized from the same intermediate. The synthetic 1 showed the same mutagenic activity as the isolated mutagen. However, 2 was non-mutagenic.