Using COC(=O)c1cc2c([nH]1)CCC2Cc1ccc(OC)c(OC)c1 to produce COc1ccc(CC2CCc3[nH]c(C(=O)O)cc32)cc1OC, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.