Numerous carbazole derivatives were designed by the Chemsketch software followed by 3D optimization. Docking studies were performed using AUTODOCK 4.2.6 software to check their binding interactions with eukaryotic topoisomerase-I, based on the crystal structure of Human Topoisomerse-I-DNA complex (PDB ID: 1A35). Results of docking studies of designed carbazole derivatives were compared on the basis of their minimum binding energy with a well known topoisomerase-I inhibitor i.e. Adriamycin,. Above results were used to find out active compounds and two series of such active compounds i.e. 2-[(4, 5-dihydro-2-substitutedphenyl)imidazol-1-ylamino]-1-(9H-carbazol-9-yl)ethanone (3a-3e) and 2-(9H-carbazol-9-yl)-N'-[{(4-substitutedphenyl)(piperazin-1-yl)} methyl] aceto hydrazide (6a-6e) were synthesized. All the synthesized compounds were characterized by IR, 1 H NMR,
13C NMR, MASS spectrometry and elemental analysis and also screened for their in vitro anticancer activity against human breast cancer cell line (MCF 7) by sulphorodamine B (SRB) assay method. GI 50 was measured by using 10, 20, 40 and 80 µg/ml concentrations of tested compounds along with the standard i.e. Adriamycin. Results revealed that the tested compounds 3a, 3d, 6c, 6d and 6e were comparable to Adriamycin having GI 50 <10µg/ml. Compound 3a and 6c were found to be most active among all the tested compounds.