two nitrosamides ( n-methyl-n'-nitro-n-nitrosoguanidine and methylnitrosourea ) and three nitrosamines ( dimethylnitrosamine , nitrosomorpholine , and dinitrosopiperazine ) and their deuterium-containing analogs were tested for reversion of a nonsense mutation in the tyr locus of escherichia coli wu 3610 ( tyr- , leu- ) .
C0028197
nitrosamines
C0012431
dimethylnitrosamine