Using Cc1csc(Nc2ncc(Br)cc2OC2CCN(C(=O)OC(C)(C)C)C2)n1, ClCCl to produce Cc1csc(Nc2ncc(Br)cc2OC2CCNC2)n1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.