title: Mutagenicity of K-region derivatives of 1-nitropyrene; remarkable activity of 1- and 3-nitro-5H-phenanthro[4,5-bcd]pyran-5-one.
abstract: The mutagenic activities toward S. typhimurium strains TA98 and TA100 of K-region derivatives of 1-nitropyrene and pyrene were determined. The compounds tested were trans-4,5-dihydro-4,5-dihydroxy-1-nitropyrene (Compound 3), trans-4,5-dihydro-4,5-dihydroxypyrene (Compound 4), 1-nitropyrene-4,5-quinone (Compound 5), 1-nitropyrene-9,10-quinone (Compound 6), pyrene-4,5-quinone (Compound 7), and the lactones, 1-nitro-5H-phenanthro[4,5-bcd]pyran-5-one (Compound 8), 3-nitro-5H-phenanthro[4,5-bcd]pyran-5-one (Compound 9), and 5H-phenanthro[4,5-bcd]pyran-5-one (Compound 10). Neither pyrene nor any of its K-region derivatives was mutagenic, either in the absence or presence of S9 mix at the doses tested. Of the K-region derivatives of 1-nitropyrene, the lactones (Compounds 8 and 9) were generally the most active; 0.25 microgram/plate induced 900-2200 revertants in TA98 or TA100 without activation. The 4,5-dihydrodiol (Compound 3), an established mammalian metabolite of 1-nitropyrene, was less mutagenic than was 1-nitropyrene in TA98, but was more mutagenic than was 1-nitropyrene in TA100, regardless of the presence of S9 mix. The quinones (Compounds 5 and 6) were less mutagenic than was 1-nitropyrene in the absence of S9 mix in both strains, but their activities were increased in the presence of S9 mix. The mutagenic activities of the lactones (Compounds 8 and 9) were lower in strains TA98NR and TA98/1,8-DNP6 than in TA98, indicating that nitro-reduction and esterification are involved in their activation. The results of this study indicate that K-region derivatives of 1-nitropyrene may be important in its metabolic activation.
mesh_terms: D000818:Animals; D055598:Chemical Phenomena; D002621:Chemistry; D004305:Dose-Response Relationship, Drug; D008297:Male; D008862:Microsomes, Liver / Q000187:drug effects; D009152:Mutagenicity Tests; D009153:Mutagens; D010616:Phenanthrenes / Q000009:adverse effects*; D011721:Pyrenes / Q000009:adverse effects*; D051381:Rats; D011916:Rats, Inbred F344; D012486:Salmonella typhimurium / Q000187:drug effects; D013329:Structure-Activity Relationship
chemical_list: D009153:Mutagens; D010616:Phenanthrenes; D011721:Pyrenes; C048542:1-nitro-5H-phenanthro(4,5-bcd)pyran-5-one; C048541:3-nitro-5H-phenanthro(4,5-bcd)pyran-5-one; C032668:1-nitropyrene