[{"from": "human", "value": "Provide a description of this molecule. [B][Branch2][Ring2][=C][C@H1][Branch1][#Branch1][C][C][Branch1][C][C][C][N][C][=Branch1][C][=O][C@H1][Branch1][=Branch1][C@@H1][Branch1][C][C][O][N][C][=Branch1][C][=O][C][=C][C][=C][C][=Branch1][Ring2][=N][Ring1][=Branch1][C][=C][C][=C][C][=C][Ring1][=Branch1][Branch1][C][O][O]"}, {"from": "gpt", "value": "The molecule is an orally bioavailable synthetic P2 threonine boronic acid inhibitor of the chymotrypsin-like activity of the proteasome, with potential antineoplastic activity. Delanzomib represses the proteasomal degradation of a variety of proteins, including inhibitory kappaBalpha (IkappaBalpha), resulting in the cytoplasmic sequestration of the transcription factor NF-kappaB; inhibition of NF-kappaB nuclear translocation and transcriptional up-regulation of a variety of cell growth-promoting factors; and apoptotic cell death in susceptible tumor cell populations. In vitro studies indicate that this agent exhibits a favorable cytotoxicity profile toward normal human epithelial cells, bone marrow progenitors, and bone marrow-derived stromal cells relative to the proteasome inhibitor bortezomib. The intracellular protein IkappaBalpha functions as a primary inhibitor of the proinflammatory transcription factor NF-kappaB."}]