Using CC(C)(C)OC(=O)Cn1ccc2cc(N3CCn4ccc(Cl)c4C3=O)ccc21 to produce O=C(O)Cn1ccc2cc(N3CCn4ccc(Cl)c4C3=O)ccc21, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.