The synthesis of 3-[3/4-(2-aryl-2-oxoethoxy) arylidene] chroman/thiochroman-4-one derivatives (1-34) and evaluation of their anticancer activities were aimed in this work. Final compounds were obtained in multistep synthesis reactions using phenol/thiophenol derivatives as starting materials. For anticancer activity evaluation, all compounds were offered to National Cancer Institute (NCI), USA and selected ones were tested against sixty human tumor cell lines derived from nine neoplastic diseases. The activity results were evaluated according to the drug screening protocol of the institute. Compounds containing thiochromanone skeleton exhibited higher anticancer activity. (C) 2017 The Authors. Production and hosting by Elsevier B.V. on behalf of King Saud University.