Using CC(C)(C)OC(=O)N[C@@H](Cc1ccccc1)C(=O)O, C=O to produce CC(C)(C)OC(=O)N1COC(=O)[C@@H]1Cc1ccccc1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.