A-366 is primarily utilized in biochemical research as a selective inhibitor of the G9a histone methyltransferase enzyme. This enzyme plays a crucial role in the methylation of histone H3, which is involved in gene expression regulation. By inhibiting G9a, A-366 helps researchers study the effects of histone methylation on chromatin structure and gene silencing. It is particularly valuable in cancer research, where abnormal histone methylation patterns are often observed, providing insights into potential therapeutic targets. Additionally, A-366 is used in epigenetic studies to explore its impact on cellular differentiation and development processes.