The synthesis and mutagenicity of the 3-ethyl analogues of the potent mutagens IQ, MeIQ, MeIQx and its 3,7-dimethyl isomer

The title compounds were synthesized and tested for mutagenicity on Salmonella typhimurium TA98 in the presence of S9 mix. All test compounds showed lower activity than their respective 3-methyl analogues (IQ compounds). The replacement of the 3-methyl by an ethyl group should not alter the chemistry of these compounds; hence, their lower mutagenic activity could merely be of steric origin.