Using CCOC(=O)c1cc(Cl)c2c(c1C)C1(CCS2(=O)=O)OCCO1 to produce Cc1c(C(=O)O)ccc2c1C1(CCS2(=O)=O)OCCO1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.