Using CCCC[Sn](CCCC)(CCCC)c1cncn1C, CCOC(=O)c1ccc(C)c(-n2cc(Br)cn2)c1 to produce CCOC(=O)c1ccc(C)c(-n2cc(-c3cncn3C)cn2)c1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.