Using BrCCBr, CC(=O)c1ccc2[nH]c3ccc4c(c3c2c1)CCC4=O to produce CC(=O)c1ccc2c(c1)c1c3c(ccc1n2CCBr)C(=O)CC3, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.