A series of seven derivatives of 1,1'-(5,6-dimethoxy-3-methyl-1-benzofuran-2,7-diyl)diethanone was
synthesized and characterized by 1HNMR and ESI MS spectra and elemental analyses. The obtained new compounds and
three halogen derivatives of benzofuran, reported in our earlier work, were tested for their cytotoxic properties in human
chronic (K562) and acute (HL60) leukemia cells, human cervical cancer (HeLa), and normal endothelial cells (HUVEC). Four
compounds (2, 3, 4, 5), which contain halogens in their structure showed significant anticancer activity. The most promising was 1,1'-[3-
(bromomethyl)-5,6-dimethoxy-1-benzofuran-2,7-diyl]diethanone (2), which was highly and selectively toxic for K562 cells (IC50 of 5µM)
and HL60 cells (IC50 of 0.1µM), which showed no cytotoxicity toward HeLa and HUVEC cells. Moreover, the observed remarkable
cytotoxicity of this compound toward K562 cells resulted from cells apoptosis.