Using CCCc1nc2c(C)cccc2n1Cc1ccc(OC(C(=O)OCC)c2ccccc2)cc1 to produce CCCc1nc2c(C)cccc2n1Cc1ccc(OC(C(=O)O)c2ccccc2)cc1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.