Using C[C@@H](O)[C@H](NC(=O)OCc1ccccc1)C(=O)O, CC(C)(C)OC(=O)[C@@H]1CCCN1 to produce C[C@@H](O)[C@H](NC(=O)OCc1ccccc1)C(=O)N1CCC[C@H]1C(=O)OC(C)(C)C, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.