Using CCOC(=O)C(C(C)=O)C(C)(C)C(Cl)CC(Cl)(Cl)Cl to produce CCOC(=O)C1(C(C)=O)C(C=C(Cl)Cl)C1(C)C, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.