Using BrC(Br)(Br)Br, O=c1ccn([C@@H]2O[C@H](CO)[C@@H](O)[C@H]2OCc2ccccc2)c(=O)[nH]1 to produce O=c1ccn([C@@H]2O[C@H](CBr)[C@@H](O)[C@H]2OCc2ccccc2)c(=O)[nH]1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.