AG18, also known as RG-50810 or Tyrphostin A23, is primarily used as a selective inhibitor of protein tyrosine kinases. It is widely applied in biological and pharmacological research to study cellular signaling pathways, particularly those involving tyrosine phosphorylation. This compound helps in understanding the role of tyrosine kinases in cell proliferation, differentiation, and apoptosis, making it valuable in cancer research. Additionally, AG18 is utilized to investigate the mechanisms of insulin signaling and glucose metabolism, providing insights into metabolic disorders like diabetes. Its ability to modulate kinase activity also makes it a useful tool in studying immune responses and inflammatory diseases.