New aniline or phenol N-mustards linked to DNA-affinity carriers (such as 9-anilinoacridines, acridines and quinolines), aminobenzamides or aminophenol ethers by a urea, carbamic acid, carbanic acid ester, hydrazineurea, hydrazinecarbamic acid ester, phenoxyurea, phenoxycarbamic acid ester linkage with improved chemical stability and anti-tumor therapeutic efficacy are provided.