Using CC(C)(C)OC(=O)N[C@@H](CCC(=O)OCc1ccccc1)C(=O)O, OC1CCCC1 to produce CC(C)(C)OC(=O)N[C@@H](CCC(=O)OCc1ccccc1)C(=O)OC1CCCC1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.