title: Microbial mutagenicity of 3- and 4-ring polycyclic aromatic sulfur heterocycles.
abstract: The stable isomers of 3- and 4-ring polycyclic aromatic sulfur heterocycles were tested for mutagenicity in the Ames standard plate incorporation test and a liquid pre-incubation modification of the Ames test. Of the 4 three-ring compounds tested, only naphtho[1,2-b]thiophene was mutagenic. Of the four-ring compounds, 7 of 13 were mutagenic in the standard Ames or pre-incubation Ames test. The highest activity for the 4-ring compounds was observed for phenanthrol[3,4-b]thiophene, a compound of approximately the same mutagenic potency in the Ames test as benzo[a]pyrene. The other active 4-ring compounds were of considerable less mutagenic potency than phenanthrol[3,4-b]thiophene. Mutagenicity for two of the 4-ring aromatic thiophenes could only be detected in the liquid pre-incubation Ames test. Salmonella typhimurium TA100 was the most sensitive strain to mutagenesis by these compounds, followed by TA98. All mutagenesis was indirect, requiring metabolic activation.
mesh_terms: D000818:Animals; D001711:Biotransformation; D008297:Male; D008862:Microsomes, Liver / Q000378:metabolism; D009152:Mutagenicity Tests; D009153:Mutagens; D009154:Mutation; D011083:Polycyclic Compounds / Q000378:metabolism / Q000633:toxicity*; D051381:Rats; D011919:Rats, Inbred Strains; D012486:Salmonella typhimurium / Q000187:drug effects; D013329:Structure-Activity Relationship; D013455:Sulfur
chemical_list: D009153:Mutagens; D011083:Polycyclic Compounds; D013455:Sulfur