Using O=C1CCC(=O)N1Br, CC(=O)Oc1ccc(CC(=O)O)cc1OC(C)=O to produce CC(=O)Oc1ccc(C(Br)C(=O)O)cc1OC(C)=O, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.