A small-molecule inhibitor of the RAS/RAF/MAPK signaling pathway with potential antineoplastic activity. Diazepinomicin binds to and inhibits Ras kinase, thereby preventing the phosphorylation and activation of proteins downstream of the Ras signal transduction pathway, including serine/threonine kinase RAF (BRAF) and extracellular signal-regulated kinases 1 and 2 (ERK1 and ERK-2). This agent also selectively binds to the peripheral benzodiazepine receptor (PBR), a receptor highly expressed in certain tumor cell types cells, inducing cell cycle arrest and apoptosis in PBR-expressing cells. Diazepinomicin can cross the blood-brain barrier (BBB).