Using O=[Mn](=O)(=O)[O-], CCOC(=O)c1cc(N2CC[C@H](NC(=O)c3[nH]c(C)c(Cl)c3Cl)[C@H](OC)C2)ncc1C=O to produce CCOC(=O)c1cc(N2CC[C@H](NC(=O)c3[nH]c(C)c(Cl)c3Cl)[C@H](OC)C2)ncc1C(=O)O, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.