Using COC(=O)CCC(=O)c1cccc(OC(C)=O)c1O, O=C([O-])[O-] to produce COC(=O)CCC(=O)c1cccc(OC(C)=O)c1OC, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.