A series of novel N3/8-disubstituted-3, 8-diazabicyclo [3.2. 1] octanes in order to improve the in vitro activity of the prototype 3, 8-bis [2-(3, 4, 5-trimethoxyphenyl) pyridyl-4-yl) methylpiperazine (1) were synthesized and evaluated by assays of growth inhibition against several tumor cell lines. Compounds 2a, b, f and m demonstrated not only growth-inhibitory activities against leukemia cancer cells, but also fairly good activities against the growth of ...