Mutagenic reactivities of 3,4-dinitrobiphenyl derivatives.

3,4-Dinitrobiphenyl derivatives were mutagenic in Salmonella typhimurium TA98, TA98/1,8-DNP6 and in TA98NR. We describe here the specific reactivity of 3,4-dinitrobiphenyl derivatives with diluted sodium hydroxide solution and the determination of the amounts of released nitrous ion. 3,4-Dinitrobiphenyl derivatives begin to release nitrous ions when treated with NaOH solution at a concentration of 10(-3) N. The behavior of 4NQO and o-dinitrobenzene was the same as that of 3,4-dinitrobiphenyl derivatives. The residues of 3,4-dinitrobiphenyl derivatives, after releasing nitrous ions, were estimated to be hydroxy-nitrobiphenyls, as by GC/MS, we found the formation of o-nitrophenol in the reaction mixture of o-dinitrobenzene with aqueous NaOH solution. 3,4,4'-Trinitrobiphenyl, 3,4,3',4'-tetranitrobiphenyl and 4NQO had reduced mutagenic potency in Salmonella typhimurium TA98 following treatment with diluted NaOH. In order to elucidate the ultimate forms of 3,4-dinitrobiphenyl derivatives, we investigated the reaction of o-dinitrobenzene as a basic model substance of 3,4-dinitrobiphenyl, with nucleic bases in the presence of NaOH in nonaqueous solvent. o-Nitrophenyl guanine and adenine adducts were obtained.