Using COC(=O)C(Cc1ccc2c(c1)OCO2)(Cc1ccc2c(c1)OCO2)C(=O)OC to produce O=C(O)C(Cc1ccc2c(c1)OCO2)Cc1ccc2c(c1)OCO2, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.