The title compds. [I; R = H, alkyl, cycloalkyl, etc.; R2 = alkyl, halo, aryl, etc.; R3 = H, halo, aryl, etc.; R4 = H, halo, alkyl], useful as inhibitors of cyclin dependent kinases for treatment, prevention, inhibition, or amelioration of one or more diseases assocd. with the CDKs such as cancer, were prepd. Thus, reacting II (prepn. given) with 4-aminomethylpyridine afforded 93% III which showed IC50 of 0.020 .mu.M and 0.029 .mu.M against CDK2 kinase (cyclin A or cyclin E-dependent). The pharmaceutical compn. comprising the compd. I, alone or in combination with other therapeutic agent, is claimed.