Using COC(=O)[C@H](CC(C)C)N(C(=O)OCC(Cl)(Cl)Cl)c1snc(C)c1Br to produce COC(=O)[C@H](CC(C)C)Nc1snc(C)c1Br, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.