Using CC(C)(C)OC(=O)N1CCC2(C1)CN(C(=O)Nc1ncc(Cl)s1)c1ccc(Br)cc12 to produce O=C(Nc1ncc(Cl)s1)N1CC2(CCNC2)c2cc(Br)ccc21, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.