Using COc1cc(C)c(NC(=O)OC(C)(C)C)c(C)c1C, BrBr to produce COc1c(C)c(C)c(NC(=O)OC(C)(C)C)c(C)c1Br, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.