Using CCOC(=O)C1C(O)=C(C(=O)CC)C(=O)CC1c1cccc(OC(=O)CC)c1 to produce CCC(=O)C1=C(O)CC(c2cccc(O)c2)CC1=O, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.