SIJ1777 is a pyrimidopyrimidinone class type II pan-BRAF inhibitor, optimized as a derivative of GNF-7. It exerts anti-tumor effects by simultaneously inhibiting the phosphorylation and activation of the MAPK pathway (MEK/ERK) and the PI3K/AKT pathway. The core advantage of SIJ1777 is its ability to maintain double-digit nanomolar GI50 values against class II/III BRAF mutants (non-V600 mutants) and NRAS-mutant melanoma cells that are insensitive to current clinical drugs (such as vemurafenib, PLX8394), effectively inducing apoptosis and blocking tumor cell migration and anchorage-independent growth.