Using O=C(Cl)OCc1ccccc1, COC(=O)[C@@H](NC(=O)OC(C)(C)C)C(C)(C)S(=O)(=O)CC(Cc1ccccc1)C(=O)O to produce COC(=O)[C@@H](NC(=O)OCc1ccccc1)C(C)(C)S(=O)(=O)CC(Cc1ccccc1)C(=O)O, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.