Using CCOC(=O)c1cc(C(=O)OCC)[nH]n1, CC(C)(C)OC(=O)CBr to produce CCOC(=O)c1cc(C(=O)OCC)n(CC(=O)OC(C)(C)C)n1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.