Using CCCC[Sn](CCCC)(CCCC)c1ccncc1, CC(C)(C)OC(=O)N1CCc2c(Br)cccc2C1 to produce CC(C)(C)OC(=O)N1CCc2c(cccc2-c2ccncc2)C1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.