Using COC(=O)COc1ccc(-c2c3ccc(OCC(=O)OC)cc3cc3sc4ccccc4c23)cc1 to produce O=C(O)COc1ccc(-c2c3ccc(OCC(=O)O)cc3cc3sc4ccccc4c23)cc1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.