Using CCCC[C@H](NC(=O)OC(C)(C)C)C(=O)N[C@@H](Cc1c[nH]cn1)C(=O)N[C@@H](CC(N)=O)C(=O)N[C@@H](CC(C)C)C(=O)NCC(=O)OCc1ccccc1 to produce CCCC[C@H](NC(=O)OC(C)(C)C)C(=O)N[C@@H](Cc1c[nH]cn1)C(=O)N[C@@H](CC(N)=O)C(=O)N[C@@H](CC(C)C)C(=O)NCC(=O)O, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.