Purvalanol A is primarily used in biochemical and pharmaceutical research as a potent inhibitor of cyclin-dependent kinases (CDKs). It plays a key role in cell cycle regulation studies by selectively blocking CDK activity, which helps scientists investigate mechanisms of cell division, apoptosis, and tumor growth. Due to its ability to cross cell membranes effectively, it is widely applied in in vitro assays to induce cell cycle arrest and study the consequences in cancer cell lines. It is also used in neuroscience research to examine neuronal survival and differentiation, as CDK inhibition can influence neurodegenerative processes. Its specificity and potency make it a valuable tool in drug discovery, particularly in developing new anticancer agents.