Using O=C1CCC(=O)N1Br, COc1ccc(CCCC2C(=O)NC(=O)NC2=O)cc1 to produce COc1ccc(CCCC2(Br)C(=O)NC(=O)NC2=O)cc1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.