Using FCCBr, CN(C)C(=O)c1cc2cnc(Nc3ccc(N4CCNCC4)cn3)nc2n1C1CCCC1 to produce CN(C)C(=O)c1cc2cnc(Nc3ccc(N4CCN(CCF)CC4)cn3)nc2n1C1CCCC1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.