Using CC(=O)O[C@H]1[C@@H](C(=O)[C@H](Cc2ccccc2)NC(=O)OCc2ccccc2)C(=O)N1N to produce CC(=O)O[C@H]1[C@@H](C(=O)[C@H](Cc2ccccc2)NC(=O)CCc2ccccc2)C(=O)N1N, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.