Using CC(=O)O, CCOC(=O)CC(=O)OCc1cccc(C(=O)c2ccc(Cl)cc2)c1 to produce O=C(O)CCc1cccc(Cc2ccc(Cl)cc2)c1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.