Using O=C([O-])[O-], CCOc1ccc(COc2ccc3c(c2)C=C(C(=O)OC)CCS3(=O)=O)cc1 to produce CCOc1ccc(COc2ccc3c(c2)C=C(C(=O)O)CC(C)S3(=O)=O)cc1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.