CLK1-IN-1 is primarily used in biochemical research to study the role of CLK1 (CDC-like kinase 1) in cellular processes. It serves as a potent and selective inhibitor of CLK1, enabling researchers to investigate the kinase's involvement in mRNA splicing regulation. By inhibiting CLK1, it helps in understanding the impact on alternative splicing events, which are crucial for gene expression and protein diversity. This compound is also utilized in studies related to diseases where CLK1 dysregulation is implicated, such as cancer and neurodegenerative disorders. Its application extends to drug discovery efforts aimed at developing therapeutic agents targeting CLK1 and related pathways.