[{"from": "human", "value": "Describe this molecule. [C][O][C][C][O][C][=Branch1][C][=O][N][C][C][C][C][C@@H1][Branch2][Ring1][=Branch1][C][=Branch1][C][=O][N][C][C][C][C][C][C][C][O][P][=Branch1][C][=O][Branch1][C][C][O][N][C][=Branch1][C][=O][O][C][C][O][C]"}, {"from": "gpt", "value": "The molecule is the sodium salt form of pegaptanib, a 28-mer RNA aptamer covalently linked to two branched 20-kD polyethylene glycol (PEG) chains, with anti-angiogenic activity. Pegaptanib binds and blocks the activity of the extracellular vascular endothelial growth factor, specifically the 165-amino acid isoform (VEGF165). This prevents VEGF165 from binding to VEGF receptors, thereby blocking angiogenesis as well as preventing VEGF165-induced increases in vessel permeability. VEGF165 is preferentially involved in pathological ocular neovascularisation."}]