Using O=C1OC(=O)c2cc(Br)ccc21, CC1(C)c2ccccc2-c2ccc(Br)cc21 to produce CC1(C)c2cc(Br)ccc2-c2ccc(C(=O)c3ccc(Br)cc3C(=O)O)cc21, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.