Using O=C(O)CN1C(=O)[C@@H](NC(CCCCNC(=O)OCc2ccccc2)C(=O)O)CSc2ccccc21 to produce NCCCCC(N[C@H]1CSc2ccccc2N(CC(=O)O)C1=O)C(=O)O, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.