Abstract: Disclosed are novel pyrazolobenzodiazepines having the formula and the pharmaceutically acceptable salts thereof, wherein R1, R2, R3 and R4 are as defined herein. These compounds inhibit cyclin-dependent kinases (CDKs), in particular CDK2. These compounds and their pharmaceutically acceptable salts, and prodrugs of said compounds, are anti-proliferative agents useful in the treatment or control of cell proliferative disorders, in particular cancer, more particularly, the treatment or control of breast, colon, lung and prostate tumors. Also disclosed are pharmaceutical compositions containing the compounds of formula I as well as intermediates useful in the preparation of the compounds of formula I.