I-BRD9 is a selective inhibitor of the BRD9 protein, which is part of the bromodomain-containing protein family involved in gene regulation through chromatin remodeling. It is primarily used in epigenetic research to probe the function of BRD9 in cellular processes such as transcription, differentiation, and proliferation. Due to its role in modulating specific chromatin complexes, I-BRD9 serves as a valuable tool compound in studying cancers and other diseases linked to dysregulated gene expression. It has been investigated in preclinical models for its potential in treating malignancies, particularly those involving SWI/SNF complex dysfunctions, such as certain sarcomas and leukemias. Additionally, I-BRD9 helps researchers dissect the contributions of BRD9 versus other bromodomain proteins like BRD4, enabling more precise understanding of epigenetic mechanisms. Its selectivity makes it useful in developing targeted therapies and validating BRD9 as a therapeutic target in drug discovery.