1-(2-Chloroethyl)-3-(4-cyclohexylphenyl) urea (cHCEU) has been shown to abrogate the presence of thioredoxin-1 into the nucleus through its selective covalent alkylation. In the present letter we have evaluated the structure–activity relationships of the substituents at positions 3 and 4 of the phenyl ring of cHCEU derivatives on cell cycle progression and thioredoxin-1 nuclear translocation. Active CEU derivatives exhibited GI50 ranging from ...