Using COC(=O)C1CCN(C(=O)OC(C)(C)C)c2ccc(Br)cc2C1=O to produce COC(=O)C1=Cc2cc(Br)ccc2N(C(=O)OC(C)(C)C)CC1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.