Bortezomib (CAS Number: 179324-69-7) Bortezomib is a therapeutic proteosome inhibitor used to treat people with multiple myeloma, a cancer of the bone marrow. Bortezomib is also used to treat people with mantle cell lymphoma, a fast-growing cancer that affects the immune system). It acts by killing the cancer cells. Anxiety, back pain, numbness, rash, itching are some of the side effects of this dhenyl-2-[(pyrazinylcarbonyl)amino]propyl]amino]butyl]-; Boronic acid, [1-[[1-oxo-3-phenyl-2-[(2-pyrazinylcarbonyl) amino]propyl]amino]-3-methylbutyrug.