Using NCCCNCCCCNC(=O)C(O)O, N=C(N)NCCCCCCC(N)=O to produce N=C(N)NCCCCCCC(=O)NC(O)C(=O)NCCCCNCCCN, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.