Using C[C@H](N)C(=O)O, O=C(Cl)C1(Br)SC=C(Br)C1Br to produce C[C@H](NC(=O)C1(Br)SC=C(Br)C1Br)C(=O)O, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.