AIM　To synthesize piperazine derivatives and screen anti-tumor compounds with higher activity and lower toxicity. METHODS　Selecting 1,4-bis(3-bromopropionyl)piperazine as leading compound, a series of 1,4-bis［3-(amino-dithiocarboxy)propionyl］ piperazine derivatives (4a-j) were synthesized through the use of aminodithiocarboxylate. All the synthetic compounds (4a-j) were tested for their anti-tumor activity against eight kinds of tumor cells. RESULTS　Compounds (4a-j) are new compounds, among them, compounds 4c, 4d and 4e showed anti-tumor activity against HL-60. The inhibition of compounds 4c, 4d and 4e against HL-60 are 44%, 90% and 70% respectively, at the concentration of 10 μmol.L-1. However, the inhibition of the other kinds of anti-tumor cells are not distinctive. CONCLUSION　These results suggest that this may be one of the effective routes to improve the anti-tumor activity and reduce the toxicity of 1,4-bis(3-bromopropionyl)piperazine.

Urea transporters (UT) play a vital role in the mechanism of urine concentration and are recognized as novel targets for the development of salt-sparing diuretics. Thus, UT inhibitors are promising for development as novel diuretics. In the present study, a novel UT inhibitor with a diarylamide scaffold was discovered by high-throughput screening. Optimization of the inhibitor led to the identification of a promising preclinical candidate,