Novel urea derivatives of alkynes have been designed, synthesized, and evaluated as potential cancer therapeutics leads. The most active 1-((3-chloromethyl) phenyl)-3-prop-2- ynylurea (1) exhibited cytotoxic effect against HELA and MCF-7 cell lines with IC50 values of 1.55 μM and 1.48 μM, respectively. Further investigation on tube formation assay in human vein umbilical cells (HUVEC) demonstrated that 1 and methyl 4-(3-(3-ethynylureido) ...