Using COCC[C@@H](COC)n1nnc2c(Cl)nc(C)cc21, Brc1cc(Br)c2c(c1)CCN2 to produce COCC[C@@H](COC)n1nnc2c(N3CCc4cc(Br)cc(Br)c43)nc(C)cc21, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.