Carcinogenicity of 5 nitrofurans, 5 nitroimidazoles, 4 nitrobenzenes, and related compounds

1 [(5 Nitrofurfurylidene)amino]hydantoin gave negative results in chronic carcinogenicity tests in rats. Carcinogenic response was moderate for 4 methyl 1 [(5 nitrofurfurylidene)amino] 2 imidazolidinone and 1 (2 hydroxyethyl) 3 [(5 nitrofurfurylidene)amino] 2 imidazolidinone, and strong for l 5 morpholinomethyl 3 [(5 nitrofurfurylidene)amino] 2 oxazolidinone hydrochloride and 1 [(5 nitrofurfurylidene)amino] 2 imidazolidinone. Several other nitrofurans, nitrobenzenes, aminobenzenes, nitroimidazoles, and related compounds were also tested for carcinogenicity with varying results. 5 Nitro 2 furamidoxime, 2 hydrazino 4 phenylthiazole, D (-) threo 1 (p nitrophenyl) 2 dichloracetamido 1,3 propanediol, 1 (2 hydroxyethyl) 2 methyl 5 nitroimidazole, and 2 amino 5 phenyl 2 oxazolin 4 one with Mg(OH)₂ gave negative results; hexamethylmelamine and 1,2 dimethyl 5 nitroimidazole were weakly tumorigenic; 4,6 diamino 2 (5 nitro 2 furyl) s triazine and its bisacetamide, formic acid 2 [4(5 nitro 2 furyl) 2 thiazolyl] hydrazide, 2 (2,2 dimethylhydrazino) 4 (5 nitro 2 furyl)thiazole, 2 hydrazino 4(p nitrophenyl)thiazole, and 2 hydrazino 4 (p aminophenyl)thiazole were strongly carcinogenic. The significance of the structural variations is discussed with respect to nitrofuran carcinogenesis and the possible carcinogenicity of other nitroaromatic compounds.