BI-3406

BI-3406 (CAS No.: 2230836-55-0) is a synthetic small-molecule protein–protein interaction inhibitor and research probe for RAS signaling pathway studies. Mechanistically, it selectively disrupts the binding of KRAS to the guanine nucleotide exchange factor SOS1, thereby limiting SOS1-mediated nucleotide exchange, reducing GTP-loaded KRAS, and attenuating downstream MAPK pathway output; in in vitro biochemical assays, it exhibits low-nanomolar activity, and in cellular systems it typically achieves pathway and proliferation inhibitory effects in the tens of nanomolar range, with more pronounced effects in KRAS-mutant models (such as DLD?1, A549, NCI?H23, NCI?H358), while showing relatively limited activity in KRAS wild-type cell lines (such as NCI?H520, A375); selectivity analysis indicates that it favors SOS1 over SOS2 and presents an overall relatively clean off-target kinase profile, but at higher concentrations it may interact with certain unexpected targets, and therefore compatibility assessment should be performed in experimental designs; this compound is commonly used to explore KRAS dependency, validate target engagement and signaling pathway regulation, establish benchmark controls for RAS pathway modulation, and support mechanism-of-action analysis, combination strategy design, and high-content screening in cellular and xenograft studies; the concentration or dosing regimen used in specific experiments should be reasonably determined according to the research objective and model characteristics; for laboratory research use only, not for human or veterinary use, clinical application, or consumption.