In this study, a new series of thiopyrimidine-5-carbonitrile derivatives incorporated with different heterocyclic moieties was synthesized and screened for their in vitro antitumor activity against human breast MCF-7, colon HCT-116 and prostate PC-3 carcinoma cell lines. Among them, N-(4-bromophenyl)-2-cyanoacetylhydrazine-1-carbothioamide 6 revealed the most potent cytotoxic activity against all tested cell lines, so it was subjected to in vitro kinase inhibitory assay against VEGFR-2 and BRAF enzymes and examined for several apoptotic parameters to elucidate its mode of action. Molecular docking simulation was done to verify the binding mode towards VEGFR-2 and afforded understandable evidence for the observed anticancer behavior.