CDK1/2/4-IN-1 (compound 3a) is a potent CDK inhibitor with IC 50 values of 1.47, 0.78 and 0.87 μM for CDK1 , CDK2 and CDK4 , respectively. CDK1/2/4-IN-1 arrests cell cycle at G2/M phase and induces apoptosis. CDK1/2/4-IN-1 elevates Bax , caspase-3 , P53 levels and decreases Bcl-2 level. CDK1/2/4-IN-1 can be used for cancer research.