Using CC[C@H](C)[C@H](NC(=O)[C@@H](NC(=O)CCCCl)C(C)C)C(=O)N[C@@H](CCSC)C(=O)OC to produce CC[C@H](C)[C@H](NC(=O)[C@H](C(C)C)N1CCCC1=O)C(=O)N[C@@H](CCSC)C(=O)O, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.