In this investigation, the reaction of 2-cyano-N-(2,4-dioxo-1,2,3,4-tetrahydropyrimidin-5-yl) acetamide (3) with dimethylformamide dimethyl acetal (DMF-DMA) to afford the corresponding (E)-2-cyano-3-(dimethylamino)-N-(2,4-dioxo-1,2,3,4-tetrahydropyrimidin-5-yl)acrylamide (4) utilizing microwave irradiation. The condensation reactions of (E)-2-cyano-3-(dimethylamino)-N-(2,4-dioxo-1,2,3,4-tetrahydro pyrimidin-5-yl) acrylamide (4) with hydrazine derivatives to afford the equivalent pyrazole derivatives 6a and 6b; respectively. Selected of the synthesized compounds demonstrated outstanding in vitro antitumor activity against HepG2 cell line. Moreover, the evaluation of the greatest utilizing of molecular docking using Auto Dock tools for compound 1-phenyl-1H-pyrazole-5-carboxamide derivative 6b which interact with 4hdq synthase complex with interaction energy score (-4.5Kcal/mol) which is greater with short distance (1.727Å and 2.027Å). Also, the optimized molecular structure of the compounds, bond length, bond angles, energy gap HOMO-LUMO, IR frequencies were observed through DFT/ B3LYP/6+31G(d) which examine the equilibrium geometry of the new pyrazoles derivatives and the stability of HOMO/LUMO molecular orbitals.