Using O=C1CCC(=O)N1Br, CC(=O)C1(C(=O)NCc2ccccc2)CCCC1 to produce O=C(CBr)C1(C(=O)NCc2ccccc2)CCCC1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.