Using CC(C)c1cc(C(C)C)c(O)c(C(C)C)c1, O=C(O)CBr to produce CC(C)c1cc(C(C)C)c(OCC(=O)O)c(C(C)C)c1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.