Using COCCn1c(C)nc2cc(C(=O)OC)c3c(c21)OC(c1ccccc1)CC3 to produce COCCn1c(C)nc2cc(C(=O)O)c3c(c21)OC(c1ccccc1)CC3, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.