Using CC(C)(C)OC(=O)NCC(N)c1ccccc1, O=C(O)c1csc(Br)c1 to produce CC(C)(C)OC(=O)NCC(NC(=O)c1csc(Br)c1)c1ccccc1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.