Using CC1(N2CCC(Cc3ccc(Cl)cc3Cl)C2=O)CCC2(CC1)OCCO2 to produce CC1(N2CCC(Cc3ccc(Cl)cc3Cl)C2=O)CCC(=O)CC1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.