G-15 is primarily used in research settings as a selective antagonist for the GPR30 receptor, also known as GPER (G protein-coupled estrogen receptor). Its main application lies in studies related to estrogen signaling pathways, where it helps scientists investigate the role of GPER in cellular responses without affecting classical estrogen receptors. This makes G-15 a valuable tool in cancer research, particularly in breast cancer, where GPER activity has been linked to tumor progression and cell proliferation. It is also used in endocrinology and pharmacology to dissect hormone-dependent mechanisms in various tissues, including cardiovascular and metabolic systems. Due to its specificity, G-15 supports the development of targeted therapies and enhances understanding of non-classical estrogen-mediated effects.