Synthesis and evaluation of anti-proliferative activity of 1,4-disubstituted phthalazines

A series of new phthalazine derivatives 3a-i and 4a-c were synthesized via the reaction of 1-chlorophthalazine derivative 2 with either N-substituted-piperazines, primary or their secondary amines. The structure of the synthesized, new compounds were characterized by spectral data. The anti-proliferative activity on human breast cancer cell line MCF-7 of the synthesized compounds was determined. The results showed that six of the test compounds (3a, 3g, 3i, and 4a-c) displayed potent cytotoxic activity ranging from 1.4 to 2.3 mu mol.