1-Ethyl-3-methyl-2-thiohydantoin 1-Ethyl-3-methyl-2-thioxoimidazolidin-4-one 4-Imidazolidinone, 1-ethyl-3-methyl-2-thioxo- 67990-13-0 EINECS 268-037-7 Hydantoin, 1-ethyl-3-methyl-2-thio- NSC 100724