This technology includes the compounds, compositions, and methods for treating CNS disorders and cancer with an inhibitor of a p21-activated kinase (PAK). PAK activation is shown to play a key role in spine morphogenesis, and attenuation of PAK can reduce, prevent or reverse defects in spine morphogenesis leading to improvements in synaptic function, cognition, and/or behavior. This could be used to treat a wide variety of CNS disorders such as schizophrenia, Alzheimer’s, Parkinson’s Disease, depression, bipolar, and many others. Additionally, the PAK family of serine/threonine kinases plays a pivotal role in physiological processes including motility, survival, mitosis, transcription, and translation. PAKs are widely expressed in a variety of tissues and activated in multiple cancer types (i.e., breast, skin, lung, colon, brain, prostate, kidney, liver). PAK inhibitors can be administered to inhibit aberrant cellular proliferation as a cancer therapy.