ABSTRACT:
A new series of pyrazolo[3,4‐
b
]pyridine and spiro‐oxindole derivatives were rationally designed, synthesized, and biologically assessed as either CDK2 or EGFR inhibitors with potential anticancer activity. The CDK2 inhibitory evaluation of pyrazolo[3,4‐
b
]pyridines
6a–g
and
7a–f
revealed that compounds
6e
,
7b
, and
7c
exhibited potent inhibition (IC₅₀ = 0.88, 1.89, and 1.23 μM, respectively), compared to roscovitine (IC₅₀ = 0.84 μM). Among the spiro‐oxindole derivatives
8a–d
, compounds
8b
and
8c
demonstrated remarkable EGFR inhibition (IC₅₀ = 0.13 and 0.09 μM, respectively) and significant activity against mutant EGFR
T790M
(IC₅₀ = 0.32 and 0.14 μM) relative to gefitinib (IC₅₀ = 0.03 and 0.18 μM, respectively). Furthermore, compounds
6e
and
8c
exhibited selective cytotoxicity versus MCF‐7 and MDA‐MB231 cancer cells, respectively, with negligible cytotoxic effects on normal Vero cells. Flow cytometric analysis confirmed that compounds
6e
and
8c
induced G1‐phase cell cycle arrest and apoptosis in MCF‐7 and MDA‐MB‐231, respectively, accompanied by a pronounced increase in the Bax/Bcl‐2 ratio, with values of 12.15 and 16.93 fold, respectively. Molecular docking studies combined with molecular dynamics simulations further supported stable ligand–protein interactions within CDK2, EGFR, and mutant EGFR
T790M
active sites, with favorable binding energies and conformational stability throughout 100 ns trajectories. Collectively, these findings identify compounds
6e
and
8c
as promising lead scaffolds for further development of CDK2 or EGFR inhibitors with potent and selective anticancer properties.