Using O=[Cr](=O)([O-])O[Cr](=O)(=O)[O-], COc1cc(C)cc2c1Sc1ccc(CO)c(OC)c1C(=O)OC2 to produce COc1cc(C)cc2c1Sc1ccc(C(=O)O)c(OC)c1C(=O)OC2, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.